Prodrug derivatives of (e)-n-methyl-n-((3-methylbenzofuran-2-yl)methyl)-3-(7-oxo-5,6,7,8-tetrahydro-1,8-naphthyridin-3-yl)acrylamide

ABSTRACT

In part, the present disclosure is directed to prodrug derivatives of (E)-N-methyl-N-((3-methylbenzofuran-2-yl)methyl)-3-(7-oxo-5,6,7,8-tetrahydro-1,8-naphthyridin-3-yl)acrylamide compounds with significant solubility and bioavailability profiles.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.14/010,166, filed Aug. 26, 2013, which is a continuation ofInternational Patent Application No. PCT/IB2013/001780, filed Jun. 19,2013, which claims priority to and the benefit of U.S. ProvisionalPatent Application No. 61/661,559, filed Jun. 19, 2012, the entirety ofeach of which are incorporated by reference herein.

BACKGROUND

Infections caused by or related to bacteria are a major cause of humanillness worldwide. Unfortunately, the frequency of resistance tostandard antibacterials has risen dramatically over the last decade,especially in relation to Staphylococcus aureus. For example, suchresistant S. aureus includes MRSA, resistant to methicillin, vancomycin,linezolid and many other classes of antibiotics, or the newly discoveredNew Delhi metallo-beta-lactamase-1 (NDM-1) type resistance that hasshown to afford bacterial resistant to most known antibacterials,including penicillins, cephalosporins, carbapenems, quinolones andfluoroquinolones, macrolides, etc. Hence, there exists an urgent, unmet,medical need for new agents acting against bacterial targets.

In recent years, inhibitors of FabI, a bacterial target involved inbacterial fatty acid synthesis, have been developed and many have beenpromising in regard to their potency and tolerability in humans,including a very promising FabI inhibitor,(E)-N-methyl-N-((3-methylbenzofuran-2-yl)methyl)-3-(7-oxo-5,6,7,8-tetrahydro-1,8-naphthyridin-3-yl)acrylamide.This compound, however, has been found to be difficult or impracticableto formulate into acceptable oral and parenteral (e.g., intravenous orsubcutaneous) formulations, and has marked insolubility, poor solutionstability, and oral bioavailability. Much effort, over a decade or more,has been expended to design and synthesize an alternative compound thatretains the significant inhibition of FabI upon administration, but hasimproved physical and chemical characteristics that finally allow forpractical oral and parenteral formulations. Up to now, no such compoundhas been identified that has adequate stability in the solid state, inaqueous solutions, together with excellent oral bioavailability that isnecessary for oral and/or a parenteral administration, and is capable ofbeing formulated into an oral and/or intravenous or intramuscular drugproduct using practical and commonly utilized methods of sterileformulation manufacture.

SUMMARY

The present disclosure is directed to specific prodrugs of the activecompound(E)-N-methyl-N43-methylbenzofuran-2-yl)methyl)-3-(7-oxo-5,6,7,8-tetrahydro-1,8-naphthyridin-3-yl)acrylamide(compound IV), a potent inhibitor of bacterial fatty acid metabolism(via inhibition of FabI). Disclosed prodrug compounds can beadministered by oral, intravenous, and/or intramuscular routes and onceadministered, undergo in vivo a biotransformation in one or more stagesto liberate the active compound. The disclosed prodrugs are surprisinglystable in the solid state while also having high aqueous solubility andbioavailability properties. For example, one or more disclosed compoundshave also been found to be surprisingly stable to sterilization by gammaradiation, and thus well suited to the production of a sterileformulation for use in the treatment of illnesses caused by bacterialinfections.

Provided herein for example, are compounds represented by:

and pharmaceutically acceptable salts thereof.

For example, provided herein is a compound represented by:

that is both surprisingly stable in crystalline form, and very solublein aqueous solutions at room temperature. (e.g. 25° C.).

BRIEF DESCRIPTION OF THE FIGURES

FIGS. 1A-F depict mean plasma time-concentration profiles of disclosedcompounds at a dose level of 5 mg/kg in male dogs and female rats, andspecifically show the pharmacokinetics of Compound IV in male dogs andfemale rats after intravenous or oral administration of Compound 9,Compound 10 and Compound 14.

FIG. 2 depicts comparative pharmacokinetics of Compound IV and Compound10 in male dogs after administration via intravenous infusion ofCompound 10.

FIGS. 3A-B depict the correlation of exposure (AUC) with oral doselevels of disclosed compounds in A) dog and B) rat and specifically showthe pharmacokinetics of Compound IV after oral administration ofCompound IV, Compound Z or Compound 10 in dogs (3A) and rats (3B).

FIGS. 4A-B depict the XRPD spectra of Compound 10.

FIG. 5 depicts the XRPD spectra of Compound 9.

FIG. 6 depicts the XRPD spectra of Compound 11.

FIG. 7 depicts the XRPD spectra of Compound 10.

DETAILED DESCRIPTION Introduction

The disclosure is generally directed to compounds that are in part e.g.,soluble and stable in water and/or in other solvents at e.g., roomtemperature at an acceptable pH such as a pH between about 4 and about8, e.g. at a pH of about 6, or about 7.

DEFINITIONS

For convenience, before further description of the present invention,certain terms employed in the specification, examples and appendedclaims are collected here. These definitions should be read in light ofthe remainder of the disclosure and understood as by a person of skillin the art. Unless defined otherwise, all technical and scientific termsused herein have the same meaning as commonly understood by a person ofordinary skill in the art.

The articles “a” and “an” are used herein to refer to one or to morethan one (i.e., to at least one) of the grammatical object of thearticle. By way of example, “an element” means one element or more thanone element.

The term “including” is used to mean “including but not limited to”.“Including” and “including but not limited to” are used interchangeably.

The term “FabI” is art-recognized and refers to the bacterial enzymebelieved to function as an enoyl-acyl carrier protein (ACP) reductase inthe final step of the four reactions involved in each cycle of bacterialfatty acid biosynthesis. This enzyme is believed to be widelydistributed in bacteria and plants.

The term “enzyme inhibitor” refers to any compound that prevents anenzyme from effectively carrying out its respective biochemical roles.Therefore a “FabI inhibitor” is any compound that inhibits FabI fromcarrying out its biochemical role. The amount of inhibition of theenzyme by any such compound will vary and is described herein andelsewhere.

The term “antibiotic agent” or “antibacterial agent” shall mean any drugthat is useful in treating, preventing, or otherwise reducing theseverity of any bacterial disorder, or any complications thereof,including any of the conditions, disease, or complications arisingtherefrom and/or described herein. Antibiotic agents include, forexample, cephalosporins, quinolones and fluoroquinolones, penicillinsand beta lactamase inhibitors, carbapenems, monobactams, macrolides andlincosamides, glycopeptides, rifampin, oxazolidinones, tetracyclines,aminoglycosides, streptogramins, sulfonamides, and the like. Othergeneral categories of antibiotic or antibacterial agents which may bepart of a subject composition include those agents known to those ofskill in the art as antibiotics and that qualify as (with defined termsbeing in quotation marks): “drug articles” recognized in the officialUnited States Pharmacopoeia or official National Formulary (or anysupplement thereto); “new drug” and “new animal drug” approved by theFDA of the U.S. as those terms are used in Title 21 of the United StatesCode; any drug that requires approval of a government entity, in theU.S. or abroad (“approved drug”); any drug that it is necessary toobtain regulatory approval so as to comply with 21 U.S.C. §355(a)(“regulatory approved drug”); any agent that is or was subject to ahuman drug application under 21 U.S.C. §379(g) (“human drug”). (Allreferences to statutory code for this definition refer to such code asof the original filing date of the provisional application of which thisapplication claims priority). Other antibiotic or antibacterial agentsare disclosed herein, and are known to those of skill in the art. Incertain embodiments, the term “antibiotic agent” does not include anagent that is a FabI inhibitor, so that the combinations of the presentinvention in certain instances will include one agent that is a FabIinhibitor and another agent that is not.

The term “illness” as used herein refers to any illness caused by orrelated to infection by an organism.

The term “bacterial illness” as used herein refers to any illness causedby or related to infection by bacteria.

The term “cis” is art-recognized and refers to the arrangement of twoatoms or groups around a double bond such that the atoms or groups areon the same side of the double bond. Cis configurations are oftenlabeled as (Z) configurations.

The term “substantially the same” when used to describe X-ray powderdiffraction patterns, is meant to include patterns in which peaks arewithin a standard deviation of ±0.2 2θ.

The term “trans” is art-recognized and refers to the arrangement of twoatoms or groups around a double bond such that the atoms or groups areon the opposite sides of a double bond. Trans configurations are oftenlabeled as (E) configurations.

The term “therapeutic agent” is art-recognized and refers to anychemical moiety that is a biologically, physiologically, orpharmacologically active substance that acts locally or systemically ina subject. Examples of therapeutic agents, also referred to as “drugs”,are described in well-known literature references such as the MerckIndex, the Physicians Desk Reference, and The Pharmacological Basis ofTherapeutics, and they include, without limitation, medicaments;vitamins; mineral supplements; substances used for the treatment,prevention, diagnosis, cure or mitigation of a disease or illness;substances which affect the structure or function of the body; orpro-drugs, which become biologically active or more active after theyhave been placed in a physiological environment. Antibiotic andantibacterial agents and Fab I inhibitors are examples of therapeuticagents.

The term “therapeutic effect” is art-recognized and refers to a local orsystemic effect in animals, particularly mammals, and more particularlyhumans caused by a pharmacologically active substance. The term thusmeans any substance intended for use in the diagnosis, cure, mitigation,treatment or prevention of disease or in the enhancement of desirablephysical or mental development and/or conditions in an animal or human.The phrase “therapeutically-effective amount” means that amount of sucha substance that produces some desired local or systemic effect at areasonable benefit/risk ratio applicable to any treatment. Thetherapeutically effective amount of such substance will vary dependingupon the subject and disease condition being treated, the weight and ageof the subject, the severity of the disease condition, the manner ofadministration and the like, which can readily be determined by one ofordinary skill in the art. For example, certain compositions of thepresent invention may be administered in a sufficient amount to producea at a reasonable benefit/risk ratio applicable to such treatment.

The term “chiral” is art-recognized and refers to molecules which havethe property of non-superimposability of the mirror image partner, whilethe term “achiral” refers to molecules which are superimposable on theirmirror image partner. A “prochiral molecule” is a molecule which has thepotential to be converted to a chiral molecule in a particular process.

The compounds of the disclosure may contain one or more chiral centersand/or double bonds and, therefore, exist as geometric isomers,enantiomers or diastereomers. The enantiomer and diastereomers may bedesignated by the symbols “(+),” “(−).” “R” or “S,” depending on theconfiguration of substituents around the stereogenic carbon atom, butthe skilled artisan will recognize that a structure may denote one ormore chiral centers implicitly. Mixtures of enantiomers or diastereomersmay be designated “(±)” in nomenclature, but the skilled artisan willrecognize that a structure may denote a chiral center implicitly.Geometric isomers, resulting from the arrangement of substituents arounda carbon-carbon double bond or arrangement of substituents around acycloalkyl or heterocyclic ring, can also exist in the compounds of thepresent invention. The symbol

denotes a bond that may be a single, double or triple bond as describedherein. Substituents around a carbon-carbon double bond are designatedas being in the “Z” or “E” configuration wherein the terms “Z” and “E”are used in accordance with IUPAC standards. Unless otherwise specified,structures depicting double bonds encompass both the “E” and “Z”isomers. Substituents around a carbon-carbon double bond alternativelycan be referred to as “cis” or “trans,” where “cis” representssubstituents on the same side of the double bond and “trans” representssubstituents on opposite sides of the double bond. The arrangement ofsubstituents around a carbocyclic ring can also be designated as “cis”or “trans.” The term “cis” represents substituents on the same side ofthe plane of the ring and the term “trans” represents substituents onopposite sides of the plane of the ring. Mixtures of compounds whereinthe substituents are disposed on both the same and opposite sides ofplane of the ring are designated “cis/trans” or “Z/E.”

The term “stereoisomers” when used herein consist of all geometricisomers, enantiomers or diastereomers. The present invention encompassesvarious stereoisomers of these compounds and mixtures thereof.Conformational isomers and rotamers of disclosed compounds are alsocontemplated.

Individual enantiomers and diastereomers of compounds of the presentinvention can be prepared synthetically from commercially availablestarting materials that contain asymmetric or stereogenic centers, or bypreparation of racemic mixtures followed by resolution methods wellknown to those of ordinary skill in the art. These methods of resolutionare exemplified by (1) attachment of a mixture of enantiomers to achiral auxiliary, separation of the resulting mixture of diastereomersby recrystallization or chromatography and liberation of the opticallypure product from the auxiliary, (2) salt formation employing anoptically active resolving agent, (3) direct separation of the mixtureof optical enantiomers on chiral liquid chromatographic columns or (4)kinetic resolution using stereoselective chemical or enzymatic reagents.Racemic mixtures can also be resolved into their component enantiomersby well known methods, such as chiral-phase gas chromatography orcrystallizing the compound in a chiral solvent. Stereoselectivesyntheses, a chemical or enzymatic reaction in which a single reactantforms an unequal mixture of stereoisomers during the creation of a newstereocenter or during the transformation of a pre-existing one, arewell known in the art. Stereoselective syntheses encompass both enantio-and diastereoselective transformations. For examples, see Carreira andKvaerno, Classics in Stereoselective Synthesis, Wiley-VCH: Weinheim,2009.

The compounds disclosed herein can exist in solvated as well asunsolvated forms with pharmaceutically acceptable solvents such aswater, ethanol, and the like, and it is intended that the inventionembrace both solvated and unsolvated forms. The compounds disclosed heremay exist in single or multiple crystalline forms or polymorphs. In oneembodiment, the compound is amorphous. In one embodiment, the compoundis a single polymorph. In another embodiment, the compound is a mixtureof polymorphs. In another embodiment, the compound is in a crystallineform.

The invention also embraces isotopically labeled compounds of theinvention which are identical to those recited herein, except that oneor more atoms are replaced by an atom having an atomic mass or massnumber different from the atomic mass or mass number usually found innature. Examples of isotopes that can be incorporated into compounds ofthe invention include isotopes of hydrogen, carbon, nitrogen, oxygen,phosphorus, fluorine and chlorine, such as ²H, ³H, ¹³C, ¹⁴C, ¹⁵N, ¹⁸O,¹⁷O ³¹P, ³²P, ³⁵S, ¹⁸F and ³⁶Cl, respectively. For example, a compoundof the invention may have one or more H atom replaced with deuterium.

Certain isotopically-labeled disclosed compounds (e.g., those labeledwith ³H and ¹⁴C) are useful in compound and/or substrate tissuedistribution assays. Tritiated (i.e., ³H) and carbon-14 (i.e., ¹⁴C)isotopes are particularly preferred for their ease of preparation anddetectability. Further, substitution with heavier isotopes such asdeuterium (i.e., ²H) may afford certain therapeutic advantages resultingfrom greater metabolic stability (e.g., increased in vivo half-life orreduced dosage requirements) and hence may be preferred in somecircumstances. Isotopically labeled compounds of the invention cangenerally be prepared by following procedures analogous to thosedisclosed in the e.g., Examples herein by substituting an isotopicallylabeled reagent for a non-isotopically labeled reagent.

The term “ED₅₀” is art-recognized. In certain embodiments, ED₅₀ meansthe effective dose of a drug which produces 50% of its maximum responseor effect, or alternatively, the dose which produces a pre-determinedresponse in 50% of test subjects or preparations. The term “LD₅₀” isart-recognized. In certain embodiments, LD₅₀ means the dose of a drugwhich is lethal in 50% of test subjects. The term “therapeutic index” isan art-recognized term that refers to the therapeutic index of a drug,defined as ED₅₀/LD₅₀.

The term “K_(i)” is art-recognized and refers to the dissociationconstant of the enzyme-inhibitor complex.

The term “antimicrobial” is art-recognized and refers to the ability ofthe compounds disclosed herein to prevent, inhibit or destroy the growthof microbes such as bacteria, fungi, protozoa and viruses.

The term “antibacterial” is art-recognized and refers to the ability ofthe compounds disclosed herein to prevent, inhibit or destroy the growthof microbes of bacteria.

The term “microbe” is art-recognized and refers to a microscopicorganism. In certain embodiments the term microbe is applied tobacteria. In other embodiments the term refers to pathogenic forms of amicroscopic organism.

The term “alkyl” as used herein refers to a saturated straight orbranched hydrocarbon, such as a straight or branched group of 1-6, 1-4,or 1-3 carbon atoms, referred to herein as C₁-C₆alkyl, C₁-C₄alkyl, andC₁-C₃alkyl, respectively. Exemplary alkyl groups include, but are notlimited to, methyl, ethyl, propyl, isopropyl, 2-methyl-1-propyl,2-methyl-2-propyl, 2-methyl-1-butyl, 3-methyl-1-butyl, 3-methyl-2-butyl,2,2-dimethyl-1-propyl, 2-methyl-1-pentyl, 3-methyl-1-pentyl,4-methyl-1-pentyl, 2-methyl-2-pentyl, 3-methyl-2-pentyl,4-methyl-2-pentyl, 2,2-dimethyl-1-butyl, 3,3-dimethyl-1-butyl,2-ethyl-1-butyl, butyl, isobutyl, t-butyl, pentyl, isopentyl, neopentyl,hexyl, etc.

Moreover, the term “alkyl” (or “lower alkyl”) includes “substitutedalkyls”, which refers to alkyl moieties having substituents replacing ahydrogen on one or more carbons of the hydrocarbon backbone. Suchsubstituents may include, for example, a hydroxyl, a carbonyl (such as acarboxyl, an alkoxycarbonyl, a formyl, or an acyl), a thiocarbonyl (suchas a thioester, a thioacetate, or a thioformate), an alkoxyl, aphosphoryl, a phosphonate, a phosphinate, a phosphate, an amino, anamido, an amidine, an imine, a cyano, a nitro, an azido, a sulfhydryl,an alkylthio, a sulfate, a sulfonate, a sulfamoyl, a sulfonamido, asulfonyl, a heterocyclyl, an aralkyl, or an aromatic or heteroaromaticmoiety. It will be understood by those skilled in the art that themoieties substituted on the hydrocarbon chain may themselves besubstituted, if appropriate. For instance, the substituents of asubstituted alkyl may include substituted and unsubstituted forms ofamino, azido, imino, amido, phosphoryl (including phosphonate,phosphinate and phosphate), sulfonyl (including sulfate, sulfonamido,sulfamoyl and sulfonate), and silyl groups, as well as ethers,alkylthios, carbonyls (including ketones, aldehydes, carboxylates, andesters), nitrile and isonitrile, and the like.

The term “aryl” is art-recognized and refers to 5-, 6- and 7-memberedsingle-ring aromatic groups that may include from zero to fourheteroatoms, for example, benzene, pyrrole, furan, thiophene, imidazole,oxazole, thiazole, triazole, pyrazole, pyridine, pyrazine, pyridazineand pyrimidine, and the like. Those aryl groups having heteroatoms inthe ring structure may also be referred to as “heteroaryl” or“heteroaromatics.” The aromatic ring may be substituted at one or morering positions with such substituents as described above, for example,halogen, azide, alkyl, aralkyl, alkenyl, alkynyl, cycloalkyl, hydroxyl,alkoxyl, amino, nitro, sulfhydryl, imino, amido, phosphonate,phosphinate, phosphate, carbonyl, carboxyl, silyl, ether, alkylthio,sulfonyl, sulfonamido, ketone, aldehyde, ester, heterocyclyl, aromaticor heteroaromatic moieties, —CF₃, —CN, or the like. The term “aryl” alsoincludes polycyclic ring systems having two or more cyclic rings inwhich two or more carbons are common to two adjoining rings (the ringsare “fused rings”) wherein at least one of the rings is aromatic, e.g.,the other cyclic rings may be cycloalkyls, cycloalkenyls, cycloalkynyls,aryls and/or heterocyclyls.

The term “aralkyl” or “arylalkyl” is art-recognized and refers to analkyl group substituted with an aryl group (e.g., an aromatic orheteroaromatic group).

The term “carbocycle” is art-recognized and refers to an aromatic ornon-aromatic ring in which each atom of the ring is carbon.

The term “cycloalkyl” as used herein refers to a monocyclic saturated orpartically unsatured hydrocarbon group of for example 3-6, or 4-6carbons, referred to herein, e.g., as “C₃₋₆cycloalkyl” or“C₄₋₆cycloalkyl,” and derived from a cycloalkane. Exemplary cycloalkylgroups include, but are not limited to, cyclohexane, cyclohexene,cyclopentane, cyclobutane, cyclopropane or cyclopentene.

The terms “halo” or “halogen” as used herein refer to F, Cl, Br, or I.

The terms “heteroaryl” as used herein refers to a monocyclic aromatic4-6 membered ring system containing one or more heteroatoms, for exampleone to three heteroatoms, such as nitrogen, oxygen, and sulfur. Wherepossible, said heteroaryl ring may be linked to the adjacent radicalthough carbon or nitrogen. Examples of heteroaryl rings include but arenot limited to furan, benzofuran, thiophene, pyrrole, thiazole, oxazole,isothiazole, isoxazole, imidazole, pyrazole, triazole, pyridine, andpyrimidine.

The terms “hydroxy” and “hydroxyl” as used herein refers to the radical—OH.

The term “nitro” is art-recognized and refers to —NO₂; the term“halogen” is art-recognized and refers to —F, —Cl, —Br or —I; the term“sulfhydryl” is art-recognized and refers to —SH; the term “hydroxyl”means —OH; and the term “sulfonyl” is art-recognized and refers to —SO₂⁻. “Halide” designates the corresponding anion of the halogens, and“pseudohalide” has the definition set forth on page 560 of “AdvancedInorganic Chemistry” by Cotton and Wilkinson, Interscience Publishers,1966.

The definition of each expression, e.g. alkyl, m, n, and the like, whenit occurs more than once in any structure, is intended to be independentof its definition elsewhere in the same structure.

The terms triflyl, tosyl, mesyl, and nonaflyl are art-recognized andrefer to trifluoromethanesulfonyl, p-toluenesulfonyl, methanesulfonyl,and nonafluorobutanesulfonyl groups, respectively. The terms triflate,tosylate, mesylate, and nonaflate are art-recognized and refer totrifluoromethanesulfonate, p-toluenesulfonate, methanesulfonate, andnonafluorobutanesulfonate functional groups and molecules that containsaid groups, respectively.

The abbreviations Me, Et, Ph, Tf, Nf, Ts, and Ms represent methyl,ethyl, phenyl, trifluoromethanesulfonyl, nonafluorobutanesulfonyl,p-toluenesulfonyl and methanesulfonyl, respectively. A morecomprehensive list of the abbreviations utilized by organic chemists ofordinary skill in the art appears in the first issue of each volume ofthe Journal of Organic Chemistry; this list is typically presented in atable entitled Standard List of Abbreviations.

Certain compounds contained in the compositions disclosed herein mayexist in particular geometric or stereoisomeric forms. In addition,polymers of the present invention may also be optically active. Thepresent disclosure contemplates all such compounds, including cis- andtrans-isomers, R- and S-enantiomers, diastereomers, (D)-isomers,(L)-isomers, the racemic mixtures thereof, and other mixtures thereof,as falling within the scope of the invention. Additional asymmetriccarbon atoms may be present in a substituent such as an alkyl group. Allsuch isomers, as well as mixtures thereof, are intended to be includedin this invention.

If, for instance, a particular enantiomer of a compound disclosed hereinis desired, it may be prepared by asymmetric synthesis, or by derivationwith a chiral auxiliary, where the resulting diastereomeric mixture isseparated and the auxiliary group cleaved to provide the pure desiredenantiomers. Alternatively, where the molecule contains a basicfunctional group, such as amino, or an acidic functional group, such ascarboxyl, diastereomeric salts are formed with an appropriateoptically-active acid or base, followed by resolution of thediastereomers thus formed by fractional crystallization orchromatographic means well known in the art, and subsequent recovery ofthe pure enantiomers.

The term “prodrug” refers to a derivative of an active compound (drug)that undergoes a transformation under the conditions of use, such aswithin the body, to release the active drug. Prodrugs are frequently,but not necessarily, pharmacologically inactive until converted into theactive drug.

It will be understood that “substitution” or “substituted with” includesthe implicit proviso that such substitution is in accordance withpermitted valence of the substituted atom and the substituent, and thatthe substitution results in a stable compound, e.g., which does notspontaneously undergo transformation such as by rearrangement,cyclization, elimination, or other reaction.

The term “substituted” is also contemplated to include all permissiblesubstituents of organic compounds. In a broad aspect, the permissiblesubstituents include acyclic and cyclic, branched and unbranched,carbocyclic and heterocyclic, aromatic and nonaromatic substituents oforganic compounds. Illustrative substituents include, for example, thosedescribed herein above. The permissible substituents may be one or moreand the same or different for appropriate organic compounds. Forpurposes of this disclosure, the heteroatoms such as nitrogen may havehydrogen substituents and/or any permissible substituents of organiccompounds described herein which satisfy the valences of theheteroatoms. This disclosure is not intended to be limited in any mannerby the permissible substituents of organic compounds.

For purposes of this invention, the chemical elements are identified inaccordance with the Periodic Table of the Elements, CAS version,Handbook of Chemistry and Physics, 67^(th) Ed., 1986-87, inside cover.Also for purposes of the disclosure, the term “hydrocarbon” iscontemplated to include all permissible compounds having at least onehydrogen and one carbon atom. In a broad aspect, the permissiblehydrocarbons include acyclic and cyclic, branched and unbranched,carbocyclic and heterocyclic, aromatic and nonaromatic organic compoundsthat may be substituted or unsubstituted.

The definition of each expression, e.g. lower alkyl, m, n, p and thelike, when it occurs more than once in any structure, is intended to beindependent of its definition elsewhere in the same structure.

The term “pharmaceutically-acceptable salts” is art-recognized andrefers to the relatively non-toxic, inorganic and organic acid additionsalts, or inorganic or organic base addition salts of compounds,including, for example, those contained in compositions of the presentinvention.

The term “treating” includes any effect, e.g., lessening, reducing,modulating, or eliminating, that results in the improvement of thecondition, disease, disorder and the like.

The term “prophylactic” or “therapeutic” treatment is art-recognized andrefers to administration to the host of one or more of the subjectcompositions. If it is administered prior to clinical manifestation ofthe unwanted condition (e.g., disease or other unwanted state of thehost animal) then the treatment is prophylactic, i.e., it protects thehost against developing the unwanted condition, whereas if administeredafter manifestation of the unwanted condition, the treatment istherapeutic (i.e., it is intended to diminish, ameliorate or maintainthe existing unwanted condition or side effects therefrom).

A “patient,” “subject” or “host” to be treated by the subject method maymean either a human or non-human animal. Non human animals includecompanion animals (e.g. cats, dogs) and animals raised for consumption(i.e. food animals), such as cows, pigs, chickens)

The term “mammal” is known in the art, and exemplary mammals includehumans, primates, bovines, porcines, canines, felines, and rodents(e.g., mice and rats).

The term “bioavailable” is art-recognized and refers to a form of thesubject disclosure that allows for it, or a portion of the amountadministered, to be absorbed by, incorporated to, or otherwisephysiologically available to a subject or patient to whom it isadministered.

The term “pharmaceutically acceptable carrier” is art-recognized andrefers to a pharmaceutically-acceptable material, composition orvehicle, such as a liquid or solid filler, diluent, excipient, solventor encapsulating material, involved in carrying or transporting anysubject composition or component thereof from one organ, or portion ofthe body, to another organ, or portion of the body. Each carrier must be“acceptable” in the sense of being compatible with the subjectcomposition and its components and not injurious to the patient. Someexamples of materials which may serve as pharmaceutically acceptablecarriers include: (1) sugars, such as dextrose, lactose, glucose andsucrose; (2) starches, such as corn starch and potato starch; (3)cellulose, and its derivatives, such as microcrystalline cellulose,sodium carboxymethyl cellulose, methyl cellulose, ethyl cellulose,hydroxypropylmethyl cellulose (HPMC), and cellulose acetate; (4)powdered tragacanth; (5) malt; (6) gelatin; (7) talc; (8) excipients,such as cocoa butter and suppository waxes; (9) oils, such as peanutoil, cottonseed oil, safflower oil, sesame oil, olive oil, corn oil andsoybean oil; (10) glycols, such as propylene glycol; (11) polyols, suchas glycerin, sorbitol, mannitol and polyethylene glycol; (12) esters,such as ethyl oleate, glyceryl behenate and ethyl laurate; (13) agar;(14) buffering agents, such as magnesium hydroxide and aluminumhydroxide; (15) alginic acid; (16) pyrogen-free water; (17) isotonicsaline; (18) Ringer's solution; (19) ethyl alcohol; (20) phosphatebuffer solutions; and (21) other non-toxic compatible substancesemployed in pharmaceutical formulations. The disclosed excipients mayserve more than one function. For example, fillers or binders may alsobe disintegrants, glidants, anti-adherents, lubricants, sweeteners andthe like.

Contemplated equivalents of the compositions described herein includecompositions which otherwise correspond thereto, and which have the samegeneral properties thereof, wherein one or more simple variations ofsubstituents or components are made which do not adversely affect thecharacteristics of the compositions of interest. In general, thecomponents of the compositions of the disclosure may be prepared by themethods illustrated in the general reaction schema and writtenprocedures as, for example, described below, or by modificationsthereof, using readily available starting materials, reagents andconventional synthesis procedures. In these reactions, it is alsopossible to make use of variants which are in themselves known, but arenot mentioned here.

The disclosed compounds can be characterized by X-ray powderdiffractometry (XRPD). An XRPD spectrum may be obtained with ameasurement error depending on measurement conditions. In particular,intensities in a XRPD may fluctuate depending on measurement conditions.Therefore, it should be understood that the compounds providing any XRPDspectra substantially the same as the disclosed spectra fall within thescope of the disclosure. Those skilled in the art can readily judge thesubstantial identity of XRPD spectra.

Generally, a measurement error of diffraction angle for a X-ray powderdiffraction is about 5% or less, and such degree of a measurement errorshould be taken into account as to diffraction angles. For example, thediffraction angles may be reported with a measurement error of ±1°, ±2°,±3°, or ±5° 2θ.

Compounds

Disclosed herein, for example, are compounds represented by formula I:

where R₁ and R₂ are each independently selected from the groupconsisting of hydrogen, an alkali metal, NH₄ ⁺, NH⁺—(R₃)₃, NH₂ ⁺—(R₃)₂,and NH₃ ⁺—(R₃), or R₁ and R₂ taken together are an alkaline earth metal;and R₃ is independently selected for each occurrence from the groupconsisting of hydrogen, C₁₋₆ alkyl-, hydroxyC₁₋₆alkyl-, aryl (e.g.,phenyl) and arylC₁₋₆alkyl (e.g. benzyl).

In certain embodiments, R₁ and R₂ are each NH₃ ⁺—(R₃); or R₁ and R₂ isH; and one of R₁ and R₂ is NH₄ ⁺ or NH₃ ⁺—(R₃). R₃ for example, may be—CH₂CH₂OH.

In certain embodiments, R₁ and R₂ are an alkali metal. Alkali metals arefound in Group 1 of the periodic table and have only one electron intheir outer shell. Examples of alkali metals are lithium, sodium, andpotassium. In certain embodiments, for example, the alkali metal issodium or potassium.

In other embodiments, R₁ and R₂ taken together are an alkaline earthmetal. Alkaline earth metals are found in Group 2 of the periodic tableand have an oxidation number of ⁺2. Examples of alkaline earth metalsare beryllium, magnesium, and calcium. In certain embodiments, forexample, the alkaline earth metal is calcium or magnesium.

In some embodiments, R₁ and R₂ taken together are a metal from Groups8-12 of the periodic table that has an oxidation number of ⁺2, such asiron, nickel, copper and zinc, or ⁺3, such as iron In certainembodiments, for example, the metal is iron or zinc.

In yet another embodiment, R₁ and R₂ are each independently selectedfrom hydrogen and an ammonium moiety represented by NH₃ ⁺—(R₃). Incertain other embodiments one of R₁ or R₂ is H; if R₁ is H, R₂ is anammonium moiety represented by N(R₃)₄ ⁺ (e.g., NH₃ ⁺—(R₃),) or if R₂ isH, R₁ is ammonium moiety represented by N(R₃)₄ ⁺ (e.g., NH₃ ⁺—(R₃),).Alternatively, both R₁ and R₂ may each be NH₃ ⁺—(R₃). In certainembodiments, the ammonium moiety is selected from the group consistingof ammonium, methylammonium, dimethylammonium, ethylammonium,diethylammonium, ethanolammonium, diethanolammomium andtriethanolammonium.

In some embodiments, for example, a provided compound is represented by:

-   ((E)-6-[(N-methyl-((3-methylbenzofuran-2-yl)methyl)amino)-3-oxoprop-1-en-1-yl)-2-oxo-3,4-dihydro-1,8-naphthyridin-1(2H)-yl]methylphosphate    bis-ethanolammonium salt; compound 10)

In other embodiments, a provided compound is represented by:

-   ((E)-6-[(N-methyl-((3-methylbenzofuran-2-yl)methyl)amino)-3-oxoprop-1-en-1-yl)-2-oxo-3,4-dihydro-1,8-naphthyridin-1(2H)-yl]methylphosphate    disodium salt; compound 9) or the compound:

-   ((E)-6-[(N-methyl-((3-methylbenzofuran-2-yl)methyl)amino)-3-oxoprop-1-en-1-yl)-2-oxo-3,4-dihydro-1,8-naphthyridin-1(2H)-yl]methylphosphate    dipotassium salt; compound 11)

In yet another embodiment, a representative compound is

-   ((E)-6-[(N-methyl-((3-methylbenzofuran-2-yl)methyl)amino)-3-oxoprop-1-en-1-yl)-2-oxo-3,4-dihydro-1,8-naphthyridin-1(2H)-yl]methylphosphate    bis-ammonium salt; compound 14).

Exemplary compounds provided herein may be represented by:

-   ((E)-6-[(N-methyl-((3-methylbenzofuran-2-yl)methyl)amino)-3-oxoprop-1-en-1-yl)-2-oxo-3,4-dihydro-1,8-naphthyridin-1(2H)-yl]methylphosphate    monoethanolammonium salt);

-   ((E)-6-[(N-methyl-((3-methylbenzofuran-2-yl)methyl)amino)-3-oxoprop-1-en-1-yl)-2-oxo-3,4-dihydro-1,8-naphthyridin-1(2H)-yl]methylphosphate    monoammonium salt);

-   ((E)-6-[(N-methyl-((3-methylbenzofuran-2-yl)methyl)amino)-3-oxoprop-1-en-1-yl)-2-oxo-3,4-dihydro-1,8-naphthyridin-1(2H)-yl]methylphosphate    monosodium salt), and:

-   ((E)-6-[(N-methyl-((3-methylbenzofuran-2-yl)methyl)amino)-3-oxoprop-1-en-1-yl)-2-oxo-3,4-dihydro-1,8-naphthyridin-1(2H)-yl]methyl    phosphate, compound V).

Contemplated herein are compounds represented by:

wherein R₁ and R₂ may independently selected from H and—C(R₁₀R₁₀)—O—C(O)—R₁₁, wherein R₁₀ is independently selected from H andC₁₋₆alkyl (e.g. methyl); R₁₁ is selected from the group consisting ofC₁₋₆ alkyl (e.g. methyl), C₃₋₆cycloalkyl, phenyl, —O—C₁₋₆ alkyl (e.g.—O—CH₃ or −O—C₂H₅), —O—C₃₋₆cycloalkyl, and −O-phenyl, or apharmaceutically acceptable salt thereof

Also provided herein are compounds represented by:

where R₂₀ is selected from the group consisting of C₁₋₆alkyl (optionallysubstituted by hydroxyl, NR₂₃NR₂₄, (wherein R₂₃ and R₂₄ areindependently selected for each occurrence from H, —C(O)—C₁₋₆alkyl,C₁₋₆alkyl or taken together form a heterocycle), hydroxyl, —O—C₁₋₆alkyl,or C(O)—C₁₋₆alkyl), —CH₂—CH(CO₂R₂₁)—NHR₂₂, —C₁₋₆alkyl-C(O)O—R₂₁, phenyland C₃₋₆cycloalky; wherein R₂₁ is independently selected from eachoccurrence from H and C₁₋₆alkyl, and R₂₂ is selected from H and—C(O)—C₁₋₆alkyl; or a pharmaceutically acceptable salt thereof

In other embodiments, provided herein are compounds represented by:

wherein R₃₀ is selected from the group consisting of H, —O—C ₁₋₆alkyl(e.g., —O-ethyl) and C₁₋₆alkyl (e.g., t-butyl), or a pharmaceuticallyacceptable salt thereof

Also provided herein are compounds represented by:

wherein R₄₀ is selected from H and C₁₋₆alkyl (e.g. methyl), or apharmaceutically acceptable salt thereof

In other embodiments, provided herein are compounds represented by:

wherein R₅₀ is an amino acid residue. For example, R₅₀ may be selectedfrom the group consisting of —CR₅₁R₅₂—NR₅₃R₅₄, wherein R₅₁ and R₅₂ areindependently selected from the group consisting of C₁₋₄alkyl optionallysubstituted by carboxy or amino (e.g., methyl, isopropyl, hydrogen), andR₅₃ and R₅₄ are hydrogen; or R₅₁ and R₅₃ taken together with the atomson which they are attached form a 5-membered ring (e.g., a prolineresidue) and R₅₂ and R₅₄ are H. In another embodiment, R₅₁ and R₅₂ areindependently selected from the group consisting of C₁₋₄alkyl optionallysubstituted by carboxy or amino (e.g., methyl, isopropyl, hydrogen), R₅₃is hydrogen, and R₅₄ is —C(O)—CR₅₅R₅₆—NR₅₇R₅₈, wherein R₅₅ and R₅₆ areindependently selected from the group consisting of C₁₋₄alkyl optionallysubstituted by carboxy or amino (e.g., methyl, isopropyl, hydrogen), andR₅₇ and R₅₈ are hydrogen; or R₅₅ and R₅₇ taken together with the atomson which they are attached form a 5-membered ring (e.g., a prolineresidue) and R₅₆ and R₅₈ are H; or a pharmaceutically acceptable saltthereof.

Also provided herein are compounds represented by:

wherein R₆₀ is NR₆₁R₆₂, wherein R₆₁ and R₆₂ may each independently beselected from the group consisting of H, C₁₋₆alkyl (optionallysubstituted by phenyl), C₃₋₆cycloalkyl, and phenyl, or taken togetherwith the nitrogen to which they are attached, form a 4-6 memberedheterocyclic ring; or a pharmaceutically acceptable salt thereof.

In another embodiment, provided herein are compounds represented by:

wherein R₇₀ is —CR₇₁R₇₂—O—R₇₃ wherein R₇₁ and R₇₂ may each independentlybe selected from the group consisting of H and C₁₋₆alkyl (optionallysubstituted by halo); and

R₇₃ is selected from the group consisting of: —C(O)—(CH₂)_(t)—X₇;—P(O)(O—R₇₄)₂ and

wherein t is 0, 1, 2, 3 or 4;

X₇ is selected from the group consisting of amino optionally substitutedby one or two C₁₋₆alkyl, heterocyclyl optionally substituted by one ormore C₁₋₆alkyl; and —O—PO₃H₂ or alkyl ester thereof;

Y₇ is selected from the group consisting of —CH₂—O—PO₃H or alkyl esterthereof, and —OPO₃H₂ or an alkyl ester thereof; and

R₇₄, may be independently selected for each occurrence from H orC₁₋₆alkyl, or a pharmaceutically acceptable salt thereof.

In certain embodiments, for example, the compounds disclosed herein,once administered, possess improved bioavailability profiles whencompared to(E)-N-methyl-N-((3-methylbenzofuran-2-yl)methyl)-3-(7-oxo-5,6,7,8-tetrahydro-1,8-naphthyridin-3-yl)acrylamide(compound IV) or salts thereof. For example, the compounds disclosedherein may possess at least 2-fold, at least 3-fold, at least 4-fold, atleast 5-fold, at least 7-fold, at least 8-fold, at least 9-fold, atleast 10-fold or at least 20-fold greater bioavailability as compared to(E)-N-methyl-N-((3-methylbenzofuran-2-yl)methyl)-3-(7-oxo-5,6,7,8-tetrahydro-1,8-naphthyridin-3-yl)acrylamideor salts thereof.

In certain embodiments, for example, the compounds disclosed, onceadministered, herein possess improved bioavailability profiles whencompared to the p-toluenesulfonic salt of(E)-N-methyl-N-((3-methylbenzofuran-2-yl)methyl)-3-(7-oxo-5,6,7,8-tetrahydro-1,8-naphthyridin-3-yl)acrylamide.For example, the compounds disclosed herein may possess at least 2-fold,at least 3-fold, at least 4, fold, at least 5-fold, at least 7-fold, atleast 8-fold, at least 9-fold, at least 10-fold or at least 20-foldgreater bioavailability (e.g. oral bioavailability) as compared to thep-toluenesulfonic salt of(E)-N-methyl-N-((3-methylbenzofuran-2-yl)methyl)-3-(7-oxo-5,6,7,8-tetrahydro-1,8-naphthyridin-3-yl)acrylamideor salts thereof.

In another aspect, disclosed herein are pharmaceutical compositionscomprising the compounds disclosed herein and a pharmaceuticallyacceptable excipient.

In certain embodiments, the composition is formulated for one of:intravenous administration, injectable administration, topicaladministration, systemic administration, aerosol administration to therespiratory epithelium, or oral administration. For example, providedhere is a composition comprising a disclosed compound andpharmaceutically acceptable excipient or carrier suitable for oraladministration, intravenous administration, subcutaneous administration,intranasal administration or a composition suitable for inhalation.

Methods

In another aspect, disclosed herein are methods of treating a bacterialinfection, comprising administering to a patient in need thereof thepharmaceutical composition comprising a disclosed compound.

In a certain embodiment, disclosed herein is a method of treating abacterial infection, comprising administering to a patient in needthereof a pharmaceutical composition that includes a disclosed compound,where when the compound is administered to said patient, provides a meanplasma level at least 2 times, at least 3 times, at least 4 times, atleast 5 times, at least 7 times, at least 8 times, at least 9 times, atleast 10 times or at least 20 times higher than that obtained byadministering the same amount of(E)-N-methyl-N-((3-methylbenzofuran-2-yl)methyl)-3-(7-oxo-5,6,7,8-tetrahydro-1,8-naphthyridin-3-yl)acrylamideor salts thereof, on a molar basis, at about 4 hours afteradministration.

In another embodiment, disclosed herein is a method of treating abacterial infection, comprising administering to a patient in needthereof a pharmaceutical composition that includes a disclosed compound,wherein when the disclosed compound is administered to said patient,provides a mean plasma level of(E)-N-methyl-N-((3-methylbenzofuran-2-yl)methyl)-3-(7-oxo-5,6,7,8-tetrahydro-1,8-naphthyridin-3-yl)acrylamideat least 2 times, at least 3 times, at least 4 times, at least 5 times,at least 7 times, at least 8 times, at least 9 times, at least 10 timesor at least 20 times higher than that obtained by administering the sameamount, on a molar basis, of p-toluenesulfonic acid salt of(E)-N-methyl-N-((3-methylbenzofuran-2-yl)methyl)-3-(7-oxo-5,6,7,8-tetrahydro-1,8-naphthyridin-3-yl)acrylamide,at about 4 hours after administration. In certain embodiments, thepatient is a human.

Also provided herein is a method for treating cystic fibrosis in apatient in need thereof, comprising administering a disclosed compound.For example, provided here is a method of treating cystic fibrosis in apatient in need thereof comprising administering by inhalation apharmaceutically effective amount of a composition comprising adisclosed compound. Alternatively, a method of treating cystic fibrosisin a patient in need thereof is provided, comprising orally, rectally orparenterally administering a disclosed compound.

In certain embodiments, disclosed herein are methods of treating a S.aureus infection (e.g., a methicillin-resistant S. aureus infection) ina patient in need thereof, comprising administering a disclosedcompound. Other contemplated methods include treating H. influenzaand/or P. aeruginosa infection in a patient in need thereof (e.g., apatient suffering from cystic fibrosis comprising administering anpharmaceutically effective amount of a disclosed compound.

For example, disclosed here is a method of treating a bacterialinfection in a patient in need thereof comprising enterally (e.g.,orally) administering a composition comprising a disclosed compound,e.g. compound 10. Such methods may further comprising administering, ina separate dosage form, an additional antibacterial or antibiotic agentas disclosed herein. Also disclosed here is a method of treating abacterial infection in a patient in need thereof comprising parenterally(e.g., intravenously, intramuscularly, or subcutaneously) administeringa composition comprising a disclosed compound, e.g. compound 10. In someembodiments, methods of treating a bacterial infection by systemicallyadministrating a pharmaceutically effective amount of a disclosedcompound are contemplated.

The terms “systemic administration,” “administered systemically,”“peripheral administration” and “administered peripherally” areart-recognized and refer to the administration of a subject composition,therapeutic or other material other than directly into the centralnervous system, such that it enters the patient's system and, thus, issubject to metabolism and other like processes, for example,subcutaneous administration.

The terms “parenteral administration” and “administered parenterally”are art-recognized and refer to modes of administration other thanenteral and topical administration, usually by injection, and includes,without limitation, intravenous, intramuscular, intraarterial,intrathecal, intracapsular, intraorbital, intracardiac, intradermal,intraperitoneal, transtracheal, subcutaneous, subcuticular,intra-articular, subcapsular, subarachnoid, intraspinal, andintrasternal injection and infusion.

Topical administration is also contemplated, for example a method oftreating an ophthalmic bacterial infection comprising topically aneffective amount of a disclosed compound.

It will be appreciated that in certain embodiments, contemplated methodsmay include administration by inhalation or intratracheal instillationof a composition (e.g. an aerosolized, pH buffered composition)comprising a disclosed compound. The “term” inhaled administration”includes administration of a substantially uniform distribution ofappropriately sized particles to the respiratory epithelium of the nose,central airways, the peripheral aspect of the lung and/or the alveolarregion of the lung. Such particles may be introduced to the patientand/or produced using an appropriate device.

Disclosed methods may also include administration of one or moreadditional agents, e.g. further comprising administering one or morefurther antibiotic agent(s). For example, disclosed herein is method oftreating a bacterial infection in a patient in need thereof, comprisingadministering an effective amount of a disclosed compound, and furtheradministering (simultaneously or sequentially) one or more antibioticagents or antibacterial agents selected from the group consisting of:vancomycin, clindamycin, macrolides, linezolid, sulfamethoxazole (and/orother sulfa agents), cephalosporins, carbapenems, tetracyclines,glycylcyclines, tobramicin, arbekacin, gentamicin, quinolones (e.g.fluoroquinolones, such as ciprofloxin, levofloxin) or pleuromutilins andcombinations thereof. For example, provided herein is a method oftreating an ophthalmic bacterial infection comprising topicallyadministering an effective amount of a disclosed compound, andoptionally further administering a fluoroquinolone and/or anaminoglycoside. In another embodiments, disclosed herein is method oftreating or ameliorating cystic fibrosis in a patient in need thereof,comprising administering an effective amount of a disclosed compound,and further administering (simultaneously or sequentially) one or moretherapeutic agents selected from the group consisting of: aztreonam,levofloxin, vancomycin, linezolid, sulfamethoxazole (and/or other sulfaagents), tobramicin, gentamicin, quinolone (e.g. fluoroquinolone) andcombinations thereof.

Another aspect of the disclosure relates to a kit comprising thepharmaceutical composition comprising the disclosed compounds andinstructions for use thereof.

Scheme 1 depicts an exemplary synthetic route and proposed mechanism forthe in vivo processing of the disclosed compounds to the biologicallyactive form, compound IV. Disclosed compounds can be administered in awater-solubilized chemical form. Once administered, thewater-solubilized compound is metabolized in-vivo in systemiccirculation and other extracellular fluid compartments to the activeantibacterial of compound IV, for example as depicted in scheme 1:

In certain embodiments, the compound below is contemplated. Suchcompound, without being limited by any theory, may also be a metaboliteupon administration in certain patient species, such as dog:

Yet another aspect of the disclosure relates to a method of preparingthe compounds disclosed herein. In certain embodiment, the disclosurerelates to a method of preparing a compound of formula II, comprisingcontacting the phosphate compound of formula III with a compound offormula IV, wherein formula II is represented by:

Formula III is represented by:

wherein:

X represents a leaving group; Pg represents a protecting group. FormulaIV is represented by:

In certain embodiments, X is a halogen,

wherein R₄ is alkyl, aryl, aralkyl, or haloalkyl. In other embodiments,X is halogen. In certain other embodiments, X is chloride.

In certain embodiments, Pg is C₁₋₆alkyl-Si(R₅)₃, wherein R₅ isC₁₋₆alkyl. In other embodiments, Pg is —(CH₂)₂—Si(CH₃)₃. In otherembodiments, Pg is C₁₋₆alkyl, for example, t-butyl.

Pg may be arylC₁₋₆alkyl, for example, benzyl. In another embodiment, Pgis C₁₋₆alkyloxycarbonyl, e.g., Pg may be t-butyloxycarbonyl.

In other embodiments, Pg is arylC₁₋₆alkyloxycarbonyl. In otherembodiments, Pg is benzyloxycarbonyl.

It will be appreciated that contacting the phosphate compound of formulaIII with a compound of formula IV may be conducted in the presence of asolvent, e.g, dimethylformamide (DMF) and/or tetrahydrofuran (THF).Contacting the phosphate compound of formula III with a compound offormula IV may further comprise adding a base such as potassiumt-butoxide (KOtBu) and/or NaH.

In certain embodiments, the method further comprises contacting aBrønsted acid (for example, trifluoroacetic acid) and a compound ofe.g., formula II to provide a compound of formula:

wherein R₁ and R₂ are described above.

In a similar manner and in some embodiments, compounds of formula BB-DD(for example) can be prepared using a reagent such as (in lieu of, e.g.,formula III):

wherein:

X represents a leaving group (e.g. halogen such as Cl); Pg represents aprotecting group (such as t-butyl or —O-ethyl).

Toxicology of Compounds

Acute toxicity can be assessed using increasing doses in mice androdents. Exploratory acute toxicity in mice and/or rats after singledose may be undertaken to begin estimation of the therapeutic window ofinhibitors and to identify the potential target organism of toxicity. Ascandidate selection nears, these studies may provide guidance for theselection of proper doses in multi-dose studies, as well as establishany species-specific differences in toxicities. These studies may becombined with routine pharmacokinetic (PK) measurements to assure properdosages were achieved. Generally 3-4 doses will be chosen that areestimated to span a range having no effect through to higher doses thatcause major toxic, but non-lethal, effects. Animals will be observed foreffects on body weight, behavior and food consumption, and aftereuthanasia, hematology, blood chemistry, urinalysis, organ weight, grosspathology and histopathology will be undertaken.

Cytotoxicity Assays

Cytotoxicity of the new compounds may be evaluated by the Alamar Blueassay according the manufacturer's instructions. Human cell lines (e.g.Jurkat) grown in 96 well plates may be exposed to serial dilutions ofthe tested compounds. After adding Alamar Blue, cell viability may bedetermined by measuring the absorbance of the reduced and oxidized formsof Alamar Blue at 570 nm and 600 nm. Cytotoxicity may be reported asLD₅₀, the concentration that causes a 50% reduction in cell viability.

Dosages

The dosage of any disclosed compositions will vary depending on thesymptoms, age and body weight of the patient, the nature and severity ofthe disorder to be treated or prevented, the route of administration,and the form of the subject composition. Any of the subject formulationsmay be administered in a single dose or in divided doses. Dosages forthe compositions may be readily determined by techniques known to thoseof skill in the art or as taught herein.

In certain embodiments, the dosage of the subject compounds willgenerally be in the range of about 0.01 ng to about 10 g per kg bodyweight, specifically in the range of about 1 ng to about 0.1 g per kg,and more specifically in the range of about 100 ng to about 10 mg perkg.

An effective dose or amount, and any possible effects on the timing ofadministration of the formulation, may need to be identified for anyparticular composition of the disclosure. This may be accomplished byroutine experiment as described herein, using one or more groups ofanimals (preferably at least 5 animals per group), or in human trials ifappropriate. The effectiveness of any subject composition and method oftreatment or prevention may be assessed by administering the compositionand assessing the effect of the administration by measuring one or moreapplicable indices, and comparing the post-treatment values of theseindices to the values of the same indices prior to treatment.

The precise time of administration and amount of any particular subjectcomposition that will yield the most effective treatment in a givenpatient will depend upon the activity, pharmacokinetics, andbioavailability of a subject composition, physiological condition of thepatient (including age, sex, disease type and stage, general physicalcondition, responsiveness to a given dosage and type of medication),route of administration, and the like. The guidelines presented hereinmay be used to optimize the treatment, e.g., determining the optimumtime and/or amount of administration, which will require no more thanroutine experimentation consisting of monitoring the subject andadjusting the dosage and/or timing.

While the subject is being treated, the health of the patient may bemonitored by measuring one or more of the relevant indices atpredetermined times during the treatment period. Treatment, includingcomposition, amounts, times of administration and formulation, may beoptimized according to the results of such monitoring. The patient maybe periodically reevaluated to determine the extent of improvement bymeasuring the same parameters. Adjustments to the amount(s) of subjectcomposition administered and possibly to the time of administration maybe made based on these reevaluations.

Treatment may be initiated with smaller dosages which are less than theoptimum dose of the compound. Thereafter, the dosage may be increased bysmall increments until the optimum therapeutic effect is attained.

The use of the subject compositions may reduce the required dosage forany individual agent contained in the compositions because the onset andduration of effect of the different agents may be complimentary.

Toxicity and therapeutic efficacy of subject compositions may bedetermined by standard pharmaceutical procedures in cell cultures orexperimental animals, e.g., for determining the LD₅₀ and the ED₅₀.

The data obtained from the cell culture assays and animal studies may beused in formulating a range of dosage for use in humans. The dosage ofany subject composition lies preferably within a range of circulatingconcentrations that include the ED₅₀ with little or no toxicity. Thedosage may vary within this range depending upon the dosage formemployed and the route of administration utilized. For compositions ofthe disclosure, the therapeutically effective dose may be estimatedinitially from cell culture assays.

Compositions are also contemplated herein that include one or more ofthe disclosed compounds with a second component. Second components insuch compositions of the present disclosure are usually an antibioticagent other than a disclosed compound. Additional components may also bepresent, including FabI inhibitors or antibiotic agents. Thecontemplated methods of treatment disclosed herein, in some embodiments,may further comprise administering another agent such as one describedbelow. For example, a method of treating a bacterial infection isprovided that comprises administering a disclosed compound and furthercomprises administering an antibiotic agent or antibacterial agentdescribed below.

Non-limiting examples of antibiotic agents that may be used in theantibacterial compositions of the disclosure include cephalosporins,quinolones and fluoroquinolones, penicillins, penicillins and betalactamase inhibitors, carbepenems, monobactams, macrolides andlincosamines, glycopeptides, rifampin, oxazolidonones, tetracyclines,aminoglycosides, streptogramins, sulfonamides, and others. Each familycomprises many members.

Cephalosporins can be further categorized by generation. Non-limitingexamples of cephalosporins by generation include the following. Examplesof cephalosporins—First generation compounds include Cefadroxil,Cefazolin, Cephalexin, Cephalothin, Cephapirin, and Cephradine. Secondgeneration compounds include Cefaclor, Cefamandol, Cefonicid, Cefotetan,Cefoxitin, Cefprozil, Ceftmetazole, Cefuroxime, Cefuroxime axetil, andLoracarbef.—Third generation include Cefdinir, Ceftibuten, Cefditoren,Cefetamet, Cefpodoxime, Cefprozil, Cefuroxime (axetil), Cefuroxime(sodium), Cefoperazone, Cefixime, Cefotaxime, Cefpodoxime proxetil,Ceftazidime, Ceftizoxime, and Ceftriaxone. Fourth generation compoundsinclude Cefepime.

Non-limiting examples of quinolones and fluoroquinolones includeCinoxacin, Ciprofloxacin, Enoxacin, Gatifloxacin, Grepafloxacin,Levofloxacin, Lomefloxacin, Moxifloxacin, Nalidixic acid, Norfloxacin,Ofloxacin, Sparfloxacin, Trovafloxacin, Oxolinic acid, Gemifloxacin, andPefloxacin.

Non-limiting examples of penicillins include Amoxicillin, Ampicillin,Bacampicillin, Carbenicillin Indanyl, Mezlocillin, Piperacillin, andTicarcillin.

Non-limiting examples of penicillins and beta lactamase inhibitorsinclude Amoxicillin-Clavulanic Acid, Ampicillin-Sulbactam,Benzylpenicillin, Cloxacillin, Dicloxacillin, Methicillin, Oxacillin,Penicillin G (Benzathine, Potassium, Procaine), Penicillin V,Piperacillin+Tazobactam, Ticarcillin+Clavulanic Acid, and Nafcillin.Non-limiting examples of carbepenems include Imipenem-Cilastatin andMeropenem.

A non-limiting example of a monobactam includes Aztreonam. Non-limitingexamples of macrolides and lincosamines include Azithromycin,Clarithromycin, Clindamycin, Dirithromycin, Erythromycin, Lincomycin,and Troleandomycin. Non-limiting examples of glycopeptides includeTeicoplanin and Vancomycin. Non-limiting examples of rifampins includeRifabutin, Rifampin, and Rifapentine. A non-limiting example ofoxazolidonones includes Linezolid. Non-limiting examples oftetracyclines include Demeclocycline, Doxycycline, Methacycline,Minocycline, Oxytetracycline, Tetracycline, and Chlortetracycline.

Non-limiting examples of aminoglycosides include Amikacin, Arbakacin,Gentamicin, Kanamycin, Sisomicin, Arbekacin, Neomycin, Netilmicin,Streptomycin, Tobramycin, and Paromomycin. A non-limiting example ofstreptogramins includes Quinopristin+Dalfopristin.

Non-limiting examples of sulfonamides include Mafenide, SilverSulfadiazine, Sulfacetamide, Sulfadiazine, Sulfamethoxazole,Sulfasalazine, Sulfisoxazole, Trimethoprim-Sulfamethoxazole, andSulfamethizole.

Non-limiting examples of other antibiotic agents include Bacitracin,Chloramphenicol, Colistimethate, Fosfomycin, Isoniazid, Methenamine,Metronidazole, Mupirocin, Nitrofurantoin, Nitrofurazone, Novobiocin,Polymyxin B, Spectinomycin, Tobramycin, Tigecycline, Trimethoprim,Colistin, Cycloserine, Capreomycin, Pyrazinamide, para-Aminosalicyclicacid, and Erythromycin ethylsuccinate+sulfisoxazole.

Formulations

Pharmaceutical compositions of the disclosure may be administered byvarious means, depending on their intended use, as is well known in theart. For example, if compositions of the disclosure are to beadministered orally, they may be formulated as tablets, capsules,granules, powders or syrups. Alternatively, formulations disclosedherein may be administered parenterally as injections (intravenous,intramuscular or subcutaneous), drop infusion preparations orsuppositories. For application by the ophthalmic mucous membrane route,the compositions disclosed herein may be formulated as eye drops or eyeointments. These formulations may be prepared by conventional means,and, if desired, the compositions may be mixed with any conventionaladditive, such as an excipient, a binder, a disintegrating agent, alubricant, a corrigent, a solubilizing agent, a suspension aid, anemulsifying agent or a coating agent. The disclosed excipients may servemore than one function. For example, fillers or binders may also bedisintegrants, glidants, anti-adherents, lubricants, sweeteners and thelike.

In formulations of the disclosure, wetting agents, emulsifiers andlubricants, such as sodium lauryl sulfate and magnesium stearate, aswell as coloring agents, release agents, coating agents, sweetening,flavoring and perfuming agents, preservatives and antioxidants may bepresent in the formulated agents.

Subject compositions may be suitable for oral, nasal (e.g., byinhalation using a dry powder formulation or a nebulized formulation),topical (including buccal and sublingual), pulmonary (including aerosoladministration), rectal, vaginal, aerosol and/or parenteral (e.g., byinjection, for example, intravenous or subcutaneous injection)administration. The formulations may conveniently be presented in unitdosage form and may be prepared by any methods well known in the art ofpharmacy. The amount of a composition that may be combined with acarrier material to produce a single dose vary depending upon thesubject being treated, and the particular mode of administration.

Methods of preparing these formulations include the step of bringinginto association compositions of the disclosure with the carrier and,optionally, one or more accessory ingredients. In general, theformulations are prepared by uniformly and intimately bringing intoassociation agents with liquid carriers, or finely divided solidcarriers, or both, and then, if necessary, shaping the product.

Formulations suitable for oral administration may be in the form ofcapsules, cachets, pills, tablets, lozenges (using a flavored basis,usually sucrose and acacia or tragacanth), powders, granules, or as asolution or a suspension in an aqueous or non-aqueous liquid, or as anoil-in-water or water-in-oil liquid emulsion, or as an elixir or syrup,or as pastilles (using an inert base, such as gelatin and glycerin, orsucrose and acacia), each containing a predetermined amount of a subjectcomposition thereof as an active ingredient. Compositions of thedisclosure may also be administered as a bolus, electuary, or paste.

In solid dosage forms for oral administration (capsules, tablets, pills,dragees, powders, granules and the like), the subject composition ismixed with one or more pharmaceutically acceptable carriers, such assodium citrate or dicalcium phosphate, and/or any of the following: (1)fillers or extenders, such as starches, dextrose, lactose, sucrose,glucose, mannitol, and/or silicic acid; (2) binders, such as, forexample, celluloses (e.g., microcrystalline cellulose, methyl cellulose,hydroxypropylmethyl cellulose (HPMC) and carboxymethylcellulose),alginates, gelatin, polyvinyl pyrrolidone, sucrose and/or acacia; (3)humectants, such as glycerol; (4) disintegrating agents, such asagar-agar, calcium carbonate, potato or tapioca starch, alginic acid,certain silicates, and sodium carbonate; (5) solution retarding agents,such as paraffin; (6) absorption accelerators, such as quaternaryammonium compounds; (7) wetting agents, such as, for example, cetylalcohol and glycerol monostearate; (8) absorbents, such as kaolin andbentonite clay; (9) lubricants, such as talc, calcium stearate,magnesium stearate, solid polyethylene glycols, sodium lauryl sulfate,and mixtures thereof; and (10) coloring agents. In the case of capsules,tablets and pills, the compositions may also comprise buffering agents.Solid compositions of a similar type may also be employed as fillers insoft and hard-filled gelatin capsules using such excipients as lactoseor milk sugars, as well as high molecular weight polyethylene glycolsand the like. The disclosed excipients may serve more than one function.For example, fillers or binders may also be disintegrants, glidants,anti-adherents, lubricants, sweeteners and the like.

Formulations and compositions may include micronized crystals of thedisclosed compounds. Micronization may be performed on crystals of thecompounds alone, or on a mixture of crystals and a part or whole ofpharmaceutical excipients or carriers. Mean particle size of micronizedcrystals of a disclosed compound may be for example about 5 to about 200microns, or about 10 to about 110 microns.

A tablet may be made by compression or molding, optionally with one ormore accessory ingredients. Compressed tablets may be prepared usingbinder (for example, gelatin, microcrystalline cellulose, orhydroxypropylmethyl cellulose), lubricant, inert diluent, preservative,disintegrant (for example, sodium starch glycolate or cross-linkedsodium carboxymethyl cellulose), surface-active or dispersing agent.Molded tablets may be made by molding in a suitable machine a mixture ofthe subject composition moistened with an inert liquid diluent. Tablets,and other solid dosage forms, such as dragees, capsules, pills andgranules, may optionally be scored or prepared with coatings and shells,such as enteric coatings and other coatings well known in thepharmaceutical-formulating art. The disclosed excipients may serve morethan one function. For example, fillers or binders may also bedisintegrants, glidants, anti-adherents, lubricants, sweeteners and thelike.

It will be appreciated that a disclosed composition may includelyophilized or freeze dried compounds disclosed herein. For example,disclosed herein are compositions that disclosed compounds crystallineand/or amorphous powder forms. Such forms may be reconstituted for useas e.g., an aqueous composition.

Liquid dosage forms for oral administration include pharmaceuticallyacceptable emulsions, microemulsions, solutions, suspensions, syrups andelixirs. In addition to the subject composition, the liquid dosage formsmay contain inert diluents commonly used in the art, such as, forexample, water or other solvents, solubilizing agents and emulsifiers,such as ethyl alcohol, isopropyl alcohol, ethyl carbonate, ethylacetate, benzyl alcohol, benzyl benzoate, propylene glycol, 1,3-butyleneglycol, oils (in particular, cottonseed, groundnut, corn, germ, olive,castor and sesame oils), glycerol, tetrahydrofuryl alcohol, polyethyleneglycols and fatty acid esters of sorbitan, cyclodextrins and mixturesthereof.

Suspensions, in addition to the subject composition, may containsuspending agents as, for example, ethoxylated isostearyl alcohols,polyoxyethylene sorbitol and sorbitan esters, microcrystallinecellulose, aluminum metahydroxide, bentonite, agar-agar and tragacanth,and mixtures thereof.

Formulations for rectal or vaginal administration may be presented as asuppository, which may be prepared by mixing a subject composition withone or more suitable non-irritating excipients or carriers comprising,for example, cocoa butter, polyethylene glycol, a suppository wax or asalicylate, and which is solid at room temperature, but liquid at bodytemperature and, therefore, will melt in the body cavity and release theactive agent. Formulations which are suitable for vaginal administrationalso include pessaries, tampons, creams, gels, pastes, foams or sprayformulations containing such carriers as are known in the art to beappropriate.

Dosage forms for transdermal administration of a subject compositionincludes powders, sprays, ointments, pastes, creams, lotions, gels,solutions, and patches. The active component may be mixed under sterileconditions with a pharmaceutically acceptable carrier, and with anypreservatives, buffers, or propellants that may be required.

The ointments, pastes, creams and gels may contain, in addition to asubject composition, excipients, such as animal and vegetable fats,oils, waxes, paraffins, starch, tragacanth, cellulose derivatives,polyethylene glycols, silicones, bentonites, silicic acid, talc and zincoxide, or mixtures thereof.

Powders and sprays may contain, in addition to a subject composition,excipients such as lactose, talc, silicic acid, aluminum hydroxide,calcium silicates and polyamide powder, or mixtures of these substances.Sprays may additionally contain customary propellants, such aschlorofluorohydrocarbons and volatile unsubstituted hydrocarbons, suchas butane and propane.

Compositions and compounds of the disclosure may alternatively beadministered by aerosol. This is accomplished by preparing an aqueousaerosol, liposomal preparation or solid particles containing thecompound. A non-aqueous (e.g., fluorocarbon propellant) suspension couldbe used. Sonic nebulizers may be used because they minimize exposing theagent to shear, which may result in degradation of the compoundscontained in the subject compositions.

Ordinarily, an aqueous aerosol is made by formulating an aqueoussolution or suspension of a subject composition together withconventional pharmaceutically acceptable carriers and stabilizers. Thecarriers and stabilizers vary with the requirements of the particularsubject composition, but typically include non-ionic surfactants(Tweens, pluronics, or polyethylene glycol), innocuous proteins likeserum albumin, sorbitan esters, oleic acid, lecithin, amino acids suchas glycine, buffers, salts, sugars or sugar alcohols. Aerosols generallyare prepared from isotonic solutions.

It should be noted that excipients given as examples may have more thanone function. For example, fillers or binders can also be disintegrants,glidants, anti-adherents, lubricants, sweeteners and the like.

Pharmaceutical compositions of this disclosure suitable for parenteraladministration comprise a subject composition in combination with one ormore pharmaceutically-acceptable sterile isotonic aqueous or non-aqueoussolutions, dispersions, suspensions or emulsions, or sterile powderswhich may be reconstituted into sterile injectable solutions ordispersions just prior to use, which may contain antioxidants, buffers,bacteriostats, solutes which render the formulation isotonic with theblood of the intended recipient or suspending or thickening agents. Forexample, provided herein is an aqueous composition that includes adisclosed compound, and may further include for example, dextrose (e.g.,about 1 to about 10 weight percent dextrose, or about 5 weight percentdextrose in water (D5W).

Examples of suitable aqueous and non-aqueous carriers which may beemployed in the pharmaceutical compositions of the disclosure includewater, ethanol, polyols (such as glycerol, propylene glycol,polyethylene glycol, and the like), and suitable mixtures thereof,vegetable oils, such as olive oil, and injectable organic esters, suchas ethyl oleate and cyclodextrins. Proper fluidity may be maintained,for example, by the use of coating materials, such as lecithin, by themaintenance of the required particle size in the case of dispersions,and by the use of surfactants.

It will be appreciated that contemplated formulations, such as oralformulations (e.g. a pill or tablet), may be formulated as controlledrelease formulation, e.g., an immediate release formulation, a delayedrelease formulation, or a combination thereof.

In certain embodiments, the subject compounds may be formulated as atablet, pill, capsule or other appropriate ingestible formulation(collectively hereinafter “tablet”). In certain embodiments, atherapeutic dose may be provided in 10 tablets or fewer. In anotherexample, a therapeutic dose is provided in 50, 40, 30, 20, 15, 10, 5 or3 tablets.

In a certain embodiment, a disclosed compound is formulated for oraladministration as a tablet, capsule, or an aqueous solution orsuspension. In another embodiment of a tablet form the tablets areformulated such that the resulting amount of antibacterial agent (orantibacterial agents) provided in 20 tablets, if taken together (e.g.,over time) once administered, would provide a dose of at least themedian effective dose (ED₅₀), e.g., the dose at which at least 50% ofindividuals exhibited the quantal effect of inhibition of bacterial cellgrowth or protection (e.g., a statistically significant reduction ininfection). In a further embodiment, tablets may be formulated such thatthe total amount of antibacterial agent (or antibacterial agents)provided upon administration in 10, 5, 2 or 1 tablets would provide atleast an ED₅₀ dose to a patient (human or non-human mammal). In otherembodiments, the amount of antibacterial agent (or antibacterial agents)provided, upon administration, in 20, 10, 5 or 2 tablets taken in a 24hour time period would provide a dosage regimen providing, on average, amean plasma level of the antibacterial agent(s) of at least the ED₅₀concentration (the concentration for 50% of maximal effect of, e.g.,inhibiting bacterial cell growth). In other embodiments less than 100times, 10 times, or 5 times the ED₅₀ is provided. In other embodiments,a single dose of tablets (1-20 tablets) provides about 0.25 mg to 1250mg of compound(s).

Likewise, compounds disclosed herein can be formulated for parenteraladministration, as for example, for subcutaneous, intramuscular orintravenous injection, e.g., the antibacterial agent can be provided ina sterile solution or suspension (collectively hereinafter “injectablesolution”). The injectable solution may be, in some embodiments,formulated such that the amount of antibacterial agent (or antibacterialagents) provided in, for example, in about 0.1 to about 200 cc bolusinjection, or a dose administered intravenously, would provide a dose ofat least the median effective dose, or less than 100 times the ED₅₀, orless than 10 or 5 times the ED₅₀. The injectable solution may beformulated such that the total amount of antibacterial agent (orantibacterial agents) provided (upon administration) in 100, 50, 25, 10,5, 2.5, or 1 cc injections would provide an ED₅₀ dose to a patient, orless than 100 times the ED₅₀, or less than 10 or 5 times the ED₅₀. Inother embodiments, the amount of antibacterial agent (or antibacterialagents) provided, upon administration, in a total volume of 100 cc, 50,25, 5 or 2 cc to be injected at least twice in a 24 hour time periodwould provide a dosage regimen providing, on average, a mean plasmalevel of the antibacterial agent(s) of at least the ED₅₀ concentration,or less than 100 times the ED₅₀, or less than 10 or 5 times the ED₅₀. Inother embodiments, a single dose injection provides about 0.25 mg to1250 mg, or about 0.25 mg to about 2500 mg of antibacterial agent.

Kits

This disclosure also provides kits for conveniently and effectivelyimplementing the methods disclosed herein. Such kits comprise anysubject composition, and a means for facilitating compliance withmethods disclosed herein. Such kits provide a convenient and effectivemeans for assuring that the subject to be treated takes the appropriateactive in the correct dosage in the correct manner. The compliance meansof such kits includes any means which facilitates administering theactives according to a method disclosed herein. Such compliance meansinclude instructions, packaging, and dispensing means, and combinationsthereof. Kit components may be packaged for either manual or partiallyor wholly automated practice of the foregoing methods. In otherembodiments involving kits, the disclosure contemplates a kit includingcompositions disclosed herein, and optionally instructions for theiruse.

The examples which follow are intended in no way to limit the scope ofthe disclosure but are provided to illustrate how to prepare and usecompounds disclosed herein. Many other embodiments of this disclosurewill be apparent to one skilled in the art.

EXAMPLES Example 1 Synthesis of Various Salt Forms of(E)-(6-[N-(methyl-((3-methylbenzofuran-2-yl)methyl)amino)-3-oxoprop-1-en-1-yl)-2-oxo-3,4-dihydro-1,8-naphthyridin-1(2H)-yl]methylphosphate—Compound V

The compounds were prepared according to the procedures described belowand as shown in Scheme 2.

Synthesis of Compound 2

Phosphorus trichloride (49.2 mL, 564 mmol) was added dropwise to a 0° C.solution of trimethylsilylethanol, compound 1, (200 g, 1.69 mol, 3 eq.)and triethylamine (160 mL, 1.15 mol, 2 eq.) in 3.5 L dichloromethane. Anexotherm was observed so the addition had to be slow enough to maintainthe temperature below 10° C. Upon complete addition, triethylaminehydrochloride precipitated and the thick slurry was stirred for 30minutes at 0° C., then 30 minutes at room temperature. Water (1 L) wasadded to clarify the solution, and the clear two-phase solution wasstirred for one hour at room temperature. The organic layer wasseparated, washed with water, dried over anhydrous sodium sulfate,filtered and the filtrate concentrated under vacuum at 25-50° C. toremove residual volatiles. The reaction afforded 150 g (99%) of compound2. ¹H NMR of the material indicated >95% purity.

Compound 2 ¹H NMR (400 MHz, CDCl₃): δ 7.68 and 5.95 (2s, 1H), 4.19 (m,4H), 1.10 (m, 4H), 0.05 (s, 18H).

Synthesis of Compound 5

Phosphinic acid compound 2 (110 g in 2.5 L of water, 390 mmol) was addedto 2.5 L of water and potassium bicarbonate (22 g, 220 mmol, 0.56 eq.).The solution was placed in a 25° C. water bath and potassiumpermanganate (80 g, 506 mmol, 1.3 eq.) was added in four 20 g portionsevery twenty minutes so as not to allow the temperature of the solutionto exceed 40° C. The slurry was then heated to 50° C. for 30 minutes andthen filtered hot using a Buchner funnel and filter paper. To the clearaqueous filtrate solution was added sodium bicarbonate (115 g, 1365mmol, 3.5 eq.) followed by tetrabutylammonium hydrogensulfate (13.3 g,39 mmol, 0.1 eq.). Dichloromethane (1.5 L) was added and the solutionwas cooled to 0° C. to which 47 mL (468 mmol, 1.2 eq.) of chloromethylchlorosulfate, 4 was added slowly. The slurry was stirred for 12 hoursas it warmed to room temperature. The organic layer was separated andthe aqueous layer was extracted once more with dichloromethane (0.5 L).The combined organic layers were dried over anhydrous sodium sulfate andconcentrated in vacuo to yield the crude product which was purified byflash chromatography (25% EtOAc/hexanes with 3% NEt₃) to yield 75 g (55%yield) of compound 5 as a colorless oil which was >95% pure as indicatedby ¹H NMR.

Compound 5: ¹H NMR (400 MHz, CDCl₃): δ 5.68 (d, 2H), 4.20 (m, 4H), 1.13(m, 4H), 0.05 (s, 18H).

Synthesis of Compound IV Free Base:

Compound IV as the tosylate monohydrate salt (100 g, 183 mmol) wasplaced in methanol (3 L) and ethyl acetate (500 mL) and heated to 65° C.over a 2-hour period. To the hot suspension was added sodium hydroxide(150 mL of a 2N solution, 300 mmol) and the resultant slurry was stirredfor 30 minutes. The reaction was cooled to room temperature and thesolid was filtered. The solid was washed with water (2×500 mL) followedby ether (500 mL). The white cake was dried under vacuum overnight toyield 61.7 g (90% yield) of pure compound IV free base as an off-whitesolid.

Compound IV (free base): ¹H NMR (400 MHz, DMSO d₆): δ 10.65 (s, 1H),8.36 (m, 1H), 8.08 (m, 1H), 7.58-7.18 (m, 6H), 5.00, 4.80 (2s, 2H), 3.18(s, 2H), 2.92 (m, 3H), 2.50 (m, 2H), 2.25 (s, 3H).

Synthesis of Compound 7:

Compound IV free base (37.5 g, 100 mmol) was placed in DMF (1000 mL),cooled to −40° C. and KOtBu (12.3 g, 110 mmol, 1.1 eq.) was added inportions. The solution was stirred for 90 minutes upon which compound 5(64 g, 184 mmol, 1.84 eq., dissolved in 50 mL of DMF), was added over 15minutes. The yellow orange solution was stirred for an additional twohours as it warmed to −28° C. The dark orange solution was stirred for1.5 hours as it warmed to −10° C. and then a further 1.5 hours as itwarmed to −5° C. The reaction was quenched with dilute aqueous ammoniumchloride (1 L) followed by water (2 L) and the organic layer wasextracted twice with ethyl acetate (EtOAc, 2 L). The organic phases wereback-extracted with water (1 L), dried over anhydrous sodium sulfate,filtered and concentrated in vacuo, to give the crude product which waspurified by flash chromatography (1 kg of silica gel using 50-100%EtOAc/hexanes) to yield 41 g (60% yield) of pure 7 as a viscous brightyellow oil.

Compound 7 ¹H NMR (400 MHz, DMSO d₆): δ 8.52 (d, 1H), 8.20 (d, 1H),7.55-7.21 (m, 6H), 5.93 (s, 2H), 5.00-4.80 (2s from rotamers, 2H), 4.00(m, 4H), 3.18-2.92 (2s from rotamers, 3H), 2.92 (m, 2H), 2.25 (s, 3H),0.97 (t, 4H), 0.00 (s, 18H).

Analogs of compound 7 (as represented by Formula II, above) may beprepared using different analogs of compound 5, (as represented byFormula III, above) together with a solvent and a base, as describedabove. The table below indicates the significance of compound 5.Different Pg's used in compound III to produce compound II are shownbelow.

Pg Base Solvent Comments CH₂CH₂TMS KOtBu DMF 50% (large scale) to 70%(small scale) conversion Ethyl KOtBu DMF No detectable producttert-butyl KOtBu DMF No detectable product Benzyl KOtBu DMF Nodetectable product NaH THF No detectable product

Synthesis of Compound 8:

Compound 7 (96 g, 140 mmol) was dissolved in dichloromethane (560 mL),cooled to −25° C. and trifluoroacetic acid (187 mL, 2520 mmol, 18 eq.)in 85 mL of dichloromethane was added slowly over 15 minutes whilemaintaining the temperature below −15° C. The solution was stirred for45 minutes as it warmed to −5° C., then re-cooled to −35° C. and 300 mLof 10M NH₄OH in 350 mL of water was added slowly over 20 minutes whilemaintaining the temperature below 0° C. The solution was warmed to roomtemperature, the volatile dichloromethane solvent was removed in vacuoand the resulting milky aqueous solution was filtered to removeinsoluble reaction by-products. The filtrate was concentrated in vacuousing added toluene (2×1 L) to remove residual water, yielding a paleyellow sticky solid. This solid was suspended in 95% ethanol (3.5 L) andstirred for 3 hours at 60° C., followed by stirring at room temperaturefor overnight. The solid was then filtered, air dried, suspended in 95%ethanol (3.5 L) and isolated by filtration to produce a pale yellowbrittle solid powder. The solid was ground to a fine off-white powderwith a mortar and pestle to provide 43 g (88.6 mmol, 63% yield) ofCompound 8((E)-6-[(N-methyl-((3-methylbenzofuran-2-yl)methyl)amino)-3-oxoprop-1-en-1-yl)-2-oxo-3,4-dihydro-1,8-naphthyridin-1(2H)-yl]methylphosphateammonium salt) at >98% purity by HPLC. Note: the number of ammoniumcations in 8 was unknown.

Compound 8: ¹H NMR (400 MHz, DMSO d₆): δ 8.49 (d, 1H), 8.10 (d, 1H),7.55-7.10 (m, 6H), 5.70 (s, 2H), 4.98-4.77 (2s from rotamers, 2H),3.18-2.90 (2s from rotamers, 3H), 2.88 (m, 2H), 2.63 (m, 2H), 2.25 (s,3H).

Synthesis of Compound 9:

Compound 8 (23.7 g, 45.6 mmol) was placed in water (300 mL) and sodiumhydroxide (880 mL of a 0.1N solution, 88 mmol, 96% of theoretical foreach acid unit) was added slowly over 5 minutes. The resulting solutionwas filtered to remove particulates. The aqueous solution was thenfreeze dried in vacuo over 3 days to yield compound 9 (23.6 g, 99%) asan off-white fluffy powder which was pure (>98%) by HPLC and ¹H NMR.Compound 9 is((E)-6-[(N-methyl-((3-methylbenzofuran-2-yl)methyl)amino)-3-oxoprop-1-en-1-yl)-2-oxo-3,4-dihydro-1,8-naphthyridin-1(2H)-yl]methylphosphatedisodium salt).

Compound 9 ¹H NMR (400 MHz D₂O): δ 8.03 (s, 1H), 7.50-6.60 (m, 7H), 5.32(m, 2H), 4.48-4.42 (2s from rotamers, 2H), 2.88-2.80 (2s from rotamers,3H), 2.70-2.21 (m, 4H), 1.85 (2s from rotamers, 3H).

Recrystallization of Compound 9

Compound 9 (1.2 g, 2.27 mmol) was added to water (16 mL) and loweredinto a 70° C. oil bath. The compound dissolved in less than 2 minutes.Then isopropyl alcohol (40 mL) was added, the heating and stirring werestopped and the mixture was left to stand overnight to induceprecipitation. The next day a white suspension was obtained. Thesuspension was stirred for 15 minutes, filtered, and the solid waswashed with isopropyl alcohol, air dried, then pumped under high vacuumgiving 0.790 g of 9 as a white crystalline solid compound 9 (>98%) byHPLC and ¹H NMR.

Alternative Synthetic Route to Compound 9

Compound 8 (2 g, 3.85 mmol) was placed in a round bottom flask and 0.5NNaOH (14.6 mL, 7.3 mmol) was added. The mixture was heated at 75° C. inan oil bath for approximately 2 minutes. The resulting solution wasfiltered on a Buchner filter. The filter was and rinsed with water andisopropyl alcohol. The filtrate and washings was stirred at roomtemperature and some seed crystals were added to the solution. The crudecompound 9 oiled out on the surface of the round bottom flask. Uponstirring, the oil solidified into a white solid. This white suspensionwas stirred for 2 hours, and then filtered. The isolated solid waswashed with isopropyl alcohol (2×), air dried, then pumped under highvacuum overnight, giving 1.76 g (3.33 mmol) of compound 9 as a whitepowder which was pure (>98%) by HPLC and ¹H NMR.

Synthesis of Compound 10:

Compound 7 (38.4 g, 55.9 mmol) was dissolved in dichloromethane (233 mL)and cooled to −20° C. (bath temperature). Trifluoroacetic acid (74.7 mL,18 eq., 1 mol) in dichloromethane (50 mL) was slowly added to themixture. The mixture was stirred at −2 to 0° C. for 15 minutes thencooled to <−30° C. (bath temperature) and ethanolamine (70.9 mL, 1.17mol) in dichloromethane (150 mL) was slowly added. The cold bath wasthen removed and the mixture left to warm to room temperature for 1hour. The mixture solidified as a crystalline mass and was diluted withdichloromethane (500 mL) and filtered. The isolated solid was washedwith dichloromethane (200 mL) and air dried. The solid was stirredovernight in isopropyl alcohol (700 mL), filtered, washed with isopropylalcohol and air dried. The resultant solid was again stirred overnightin isopropyl alcohol (700 mL), filtered, washed with isopropyl alcoholand air dried. Separately, the above sequence was performed again with aseparate batch of Compound 7 (38.4 g, 55.9 mmol) and the combined solidswere then stirred overnight in isopropyl alcohol (700 mL), filtered,washed with isopropyl alcohol and air dried. The combined solid from thetwo batches was then placed in a 65° C. water bath and stirred in 95%ethanol (1 L) overnight as it cooled to room temperature to effectcrystallization. The solid was isolated by filtration, washed withisopropyl alcohol and air dried. The solid was then again placed in a65° C. water bath and stirred in 95% ethanol (1 L) overnight as itcooled to room temperature to effect crystallization. The solid wasisolated by filtration, rinsed with isopropyl alcohol and air dried. Thesolid was suspended in water (200 mL) and heated at 50° C. until theentire solid dissolved. The solution was then filtered to remove allinsoluble solid impurities. The resulting filtrate was diluted withisopropyl alcohol (2.4 L) until the solid began to precipitate and theslurry was stirred overnight to effect crystallization. Finally, thesuspension was filtered and the solid was washed with isopropyl alcohol(200 mL) and dried to give the desired product as a white solid. Thecompound was pure (>98%) by HPLC and ¹H NMR. ¹⁹F NMR against an internalstandard (CF₃CH₂OH) indicated <500 ppm of residual trifluoroacetatesalts. The purified solid was then ground to a fine powder and placedunder vacuum overnight to give 46.1 g (68% yield) of white crystallinesolid compound 10((E)-6-[(N-methyl-((3-methylbenzofuran-2-yl)methyl)amino)-3-oxoprop-1-en-1-yl)-2-oxo-3,4-dihydro-1,8-naphthyridin-1(2H)-yl]methylphosphatebis-ethanolammonium salt). The compound was pure (>98%) by HPLC and ¹HNMR. ¹⁹F NMR against an internal standard (CF₃CH₂OH) indicated <1000 ppmof residual trifluoroacetate salts.

Compound 10 ¹H NMR (400 MHz, DMSO d₆ at 80° C.): δ 8.42 (s, 1H), 8.00(s, 1H), 7.55 (d, 1H), 7.50 (s, 1H), 7.45 (s, 1H), 5.65 (s, 2H), 4.45(bs, 2H), 3.60-3.40 (m, 8H), 3.10 (bs, 2H), 2.90 (t, 2H), 2.60 (t, 2H),2.45 (s, 3H), 2.20 (s, 3H). Compound 10 ¹³C NMR (500 MHz, D₂O): δ When achemical shift has the sign “(d)” it denotes rotamers causing doublingof the carbon signals: 173(d), 166(d), 153, 151, 148, 146(d), 139,134(d), 129(d), 126, 124(d), 122(d), 121(d), 119(d), 117(d), 113(d),110(d), 65, 57, 43(d), 41, 35(d), 30, 22, 7.0. Melting Point: 183° C.decomposes at 220° C.

Synthesis of Compound 9 from Compound 10:

Compound 10 (490 mg, 0.81 mmol) was placed in a round bottom flask, towhich was added 0.5N sodium hydroxide (3.05 mL, 1.53 mmol) and the flasklowered into a 75° C. bath. Water (2.53 mL) was then added to thesolution, followed by isopropyl alcohol (25.2 mL). The homogeneousmixture was stirred at room temperature overnight and some seed crystalswere added. After standing overnight, the compound oiled out on thesurface of the round bottom flask. More seed solids were added to theflask, and the flask was cooled over dry ice. After a white solidstarted to form, the mixture was stirred for 3 hours at roomtemperature. The solids were filtered, washed with isopropyl alcohol(2×20 mL), air dried, and then pumped under high vacuum affording 329 mgof a white powder compound 9 which was pure by ¹H NMR.

Synthesis of Compound 11

Compound 8 (1.11 g, 2.29 mmol) was placed in water (100 mL) andpotassium hydroxide (43.5 mL of a 0.1N solution, 4.35 mmol) was addedslowly over 5 minutes. All the solids went into solution and the clearsolution was filtered through filter paper to remove particulates. Theaqueous solution was then freeze dried in vacuo over 2 days to yieldCompound 11(E)-6-[(N-methyl-((3-methylbenzofuran-2-yl)methyl)amino)-3-oxoprop-1-en-1-yl)-2-oxo-3,4-dihydro-1,8-naphthyridin-1(2H)-yl]methylphosphatedipotassium salt) (1.11 grams) as a white fluffy powder was pure (>98%)by HPLC and 1H NMR.

Compound 11 ¹H NMR (400 MHz, D₂O): δ 8.00 (s, 1H), 7.47-6.58 (m, 7H),5.50 (m, 2H), 4.47-4.42 (2s from rotamers, 2H), 2.85-2.78 (2s fromrotamers, 3H), 2.68-2.40 (m, 4H), 1.92-1.90 (2s from rotamers, 3H).

Synthesis of Compound 12

Compound 9 (200 mg, 0.38 mmol) was placed in water (12 mL) and magnesiumchloride hexahydrate (85 mg, 0.42 mmol in 4 mL water) was added slowly.A white solid began to appear almost immediately, the mixture wasstirred overnight, the solid filtered, washed with water, air dried andthen pumped under high vacuum to yield 12 (120 mg) as a white powderwhich could not be fully analyzed by HPLC or ¹H NMR spectra due toinsolubility. Compound 12 is(E)-6-[(N-methyl-((3-methylbenzofuran-2-yl)methyl)amino)-3-oxoprop-1-en-1-yl)-2-oxo-3,4-dihydro-1,8-naphthyridin-1(2H)-yl]methylphosphate magnesium salt.

Synthesis of Compound 13:

Compound 9 (200 mg, 0.38 mmol) was placed in water (12 mL) and calciumchloride dihydrate (61 mg, 0.41 mmol in 4 mL water) was added slowly. Awhite solid was formed and the mixture was stirred overnight. Theresulting white solid was filtered, washed with water, air dried andthen pumped under high vacuum to yield 13((E)-6-[(N-methyl-((3-methylbenzofuran-2-yl)methyl)amino)-3-oxoprop-1-en-1-yl)-2-oxo-3,4-dihydro-1,8-naphthyridin-1(2H)-yl]methylphosphatecalcium salt) as a white powder (100 mg) which could not be fullyanalyzed by HPLC or ¹H NMR due to its insolubility.

Preparation of Compound 14

Compound 8 (1.11 g, 2.29 mmol) was placed in water (100 mL) and ammoniumhydroxide 0.1M (23 mL, 2.3 mmol) was added slowly. All the solids wentinto solution and the clear solution was filtered through filter paperto remove particulates. The aqueous solution was then freeze dried over2 days to yield 14 (1.1 grams) as a white fluffy amorphous powder whichwas analytically pure (>98%) by HPLC and 1H NMR. Compound 14((E)-6-[(N-methyl-((3-methylbenzofuran-2-yl)methyl)amino)-3-oxoprop-1-en-1-yl)-2-oxo-3,4-dihydro-1,8-naphthyridin-1(2H)-yl]methylphosphatediammonium salt) is a more water-soluble amorphous form compared to lesswater soluble compound 8.

Compound 14: 1H NMR (400 MHz, D₂O): δ 8.10 (d, 1H), 7.63-6.75 (m, 7H),5.62 (m, 2H), 4.52 (s, 2H), 2.95-2.87 (2s from rotamers, 3H), 2.77-2.50(m, 4H), 2.05-2.03 (2s from rotamers, 3H).

Synthesis of Compound 15

Compound 7 (1 g, 1.46 mmol) was dissolved in dichloromethane (6 mL) andcooled to −10° C. (bath temperature), to this was slowly addedtrifluoroacetic acid (1.95 mL, 26.2 mmol) in dichloromethane (0.9 mL).The mixture was stirred at −10° C. for 15 minutes then cooled to <−30°C. (bath temperature) and methylamine (40% in water/3.88 mL) was slowlyadded. The cold bath was then removed and the mixture left to warm toroom temperature. The mixture was concentrated, suspended in toluene andconcentrated (repeated 4×) to remove water and the residue pumped underhigh vacuum to dryness. The residue was stirred overnight in 5%isopropanol/diethyl ether, the solid filtered, stirred in (5%isopropanol/diethylether) and the solid filtered. The solid obtained wasthen suspended and stirred in 30 mL of isopropyl alcohol (60° C. 1 hr,then 3 days at room temperature) filtered and the solid stirred in 30 mLof isopropyl alcohol (60° C. 4 hr, then room temperature overnight) andfiltered. This solid was then washed with isopropanol, air dried andvacuum dried yielding 330 mg of compound 15 as a white powder which wasanalytically pure (>97%) by HPLC and ¹H NMR.((E)-6-[(N-methyl-((3-methylbenzofuran-2-yl)methyl)amino)-3-oxoprop-1-en-1-yl)-2-oxo-3,4-dihydro-1,8-naphthyridin-1(2H)-yl]methylphosphatemonobasic methylammonium salt.)

Compound 15 ¹H NMR (400 MHz, D₂O): δ 7.87 (d, 1H), 7.22-6.35 (m, 7H),5.45 (br s, 2H), 4.30-4.22 (2s from rotamers, 2H), 2.64-2.62 (2s fromrotamers, 3H), 2.50-2.27 (m, 7H), 1.75-1.70 (2s from rotamers, 3H).

Synthesis of Compound 16:

Compound 7 (2.1 g, 3.06 mmol) was dissolved in dichloromethane (12 mL)and cooled to −10° C. (bath temperature), to this was slowly addedtrifluoroacetic acid (4.09 mL, 55 mmol) in dichloromethane (2 mL). Themixture was stirred at −10° C. for 15 minutes then cooled to <−30° C.(bath temperature) and dimethylamine (40% in water, 1.9 mL) was slowlyadded. The cold bath was then removed and the mixture left to warm toroom temperature. The mixture was concentrated, diluted with toluene andconcentrated (repeated 4×) to remove water, and the residue pumped underhigh vacuum to dryness. The residue was stirred overnight in 5 mLisopropanol/50 mL diethylether, and the solid filtered. The solidresidue obtained was then suspended in 60 mL of isopropyl alcohol (65°C. for 2 hours followed by room temperature overnight), filtered, washedwith isopropyl alcohol, air dried, and this purification process wasrepeated a second time. The solid was pumped under high vacuum overnightgiving 732 mg of Compound 16 as a white powder.((E)-6-[(N-methyl-((3-methylbenzofuran-2-yl)methyl)amino)-3-oxoprop-1-en-1-yl)-2-oxo-3,4-dihydro-1,8-naphthyridin-1(2H)-yl]methylphosphatemonobasic dimethylammonium salt).

Compound 16: 1H NMR (400 MHz, D₂O): δ 7.92 (s, 1H), 7.33-6.43 (m, 7H),5.50 (s, 2H), 4.35-4.30 (2s from rotamers, 2H), 2.75-2.73 (2s fromrotamers, 3H), 2.58-2.27 (m, 10H), 1.82 (s, 3H).

Synthesis of Compound 17:

Compound 7 (1.95 g, 2.84 mmol) was dissolved in dichloromethane (12 mL)and cooled to −10° C. (bath temperature). Trifluoroacetic acid (3.8 mL,51 mmol) in dichloromethane (3 mL) was slowly added to the cooledsolution. The mixture was stirred at −10° C. for 15 minutes then cooledto <−30° C. (bath temperature) and triethanolamine (7.9 mL, 60 mmol) indichloromethane (3 mL) was slowly added. The cold bath was then removedand the mixture left to warm to room temperature. The mixture wassuspended in 10% isopropyl alcohol/diethyl ether (20 mL), stirredovernight and filtered, to yield a solid which consisted of product andundesired salts. The filtrates were evaporated to dryness and theresidue was triturated with 10% isopropyl alcohol/diethyl ether. Afterthe 2 washes in 10% isopropanol/diethylether, the desired compoundcrystallized and was washed with isopropyl alcohol (2×20 mL), filteredand air dried. The desired compound 17 was pure by ¹H NMR.((E)-6-[(N-methyl((3-methylbenzofuran-2-yl)methyl)amino)-3-oxoprop-1-en-1-yl)-2-oxo-3,4-dihydro-1,8-naphthyridin-1(2H)-yl]methylphosphatemonobasic triethanolammonium salt).

Compound 17: ¹H NMR (400 MHz D₂O): δ 8.05 (m, 1H), 7.58-6.70 (m, 7H),5.60 (br s, 2H), 4.58-4.54 (2s from rotamers, 2H), 3.78 (br s, 6H), 3.30(br s, 6H), 3.08, 1.97 (m, 10H).

Synthesis of Compound 18:

Compound 7 (2.2 g, 3.2 mmol) was dissolved in dichloromethane (13 mL)and cooled to −10° C. (bath temperature), to this was slowly addedtrifluoroacetic acid (4.3 mL, 58 mmol) in dichloromethane (3 mL). Themixture was stirred at −10° C. for 15 minutes, then cooled to <−30° C.(bath temperature) and diethylamine (6.95 mL) in dichloromethane (3 mL)was slowly added. The cold bath was then removed and the mixture left towarm to room temperature. The mixture was concentrated on theevaporator. The residue crystallized on stirring in ethyl acetate. Thesolid was filtered then washed 3 times in isopropyl alcohol (iPrOH),filtered, and air dried to afford 1.1 g of the desired Compound 18((E)-6-[(N-methyl-((3-methylbenzofuran-2-yl)methyl)amino)-3-oxoprop-1-en-1-yl)-2-oxo-3,4-dihydro-1,8-naphthyridin-1(2H)-yl]methylphosphatemonobasic diethylammonium salt).

Compound 18: ¹H NMR (400 MHz, DMSO d₆): δ 8.45 (d, 1H), 8.13 (d, 1H),7.55-7.12 (m, 6H), 6.70 (s, 2H), 4.97, 4.77 (2s, 2H), 3.85 (q, 4H),3.18-2.25 (m, 10H), 1.15 (t, 6H).

An alternate synthetic route to key intermediate compound 7 is describedbelow in Scheme 3. Key intermediate, compound 7 is then converted totarget compound 10 as described in Scheme 2.

Synthesis of compound 20:

Oxalyl chloride (193 μL, 2.21 mmol, 2.0 eq.) was added dropwise, at roomtemperature to a solution of commercially available compound 19 (300 mg,1.07 mmol) and DMF (one drop) in dichloromethane (17 mL). The reactionmixture was stirred at room temperature for 4 hours. Water (30 mL) wasadded to the reaction and the two phases were separated. The aqueouslayer was extracted twice with dichloromethane. The combined organiclayers were washed with saturated brine solution, dried over anhydroussodium sulfate, filtered and concentrated in vacuo to yield 300 mg (90%yield) of the desired acid chloride 20. This material was used withoutfurther purification.

Synthesis of compound 21:

Methylamine (40% in water, 189 μL, 5.39 mmol, 3.5 eq.) was addeddropwise at 0° C. to a solution of compound 20 (300 mg, 1.54 mmol) indichloromethane (15 mL). The reaction mixture was warmed to roomtemperature and stirred for 2 hours. Water (50 mL) was added to thereaction and the two phases were separated. The aqueous layer wasextracted twice with dichloromethane. The combined organic layers werewashed with saturated brine solution, dried over anhydrous sodiumsulfate, filtered and the filtrate concentrated in vacuo to yield 291 mg(100% yield) of the desired amide 21. This material was used withoutfurther purification.

Synthesis of compound 22:

To a stirred solution of compound 21 (286 mg, 1.51 mmol) in THF (12 mL)was added LiAlH₄ (75 mg, 1.96 mmol, 1.3 eq.) portionwise at roomtemperature. The reaction mixture was stirred and heated to reflux for 5hours and then cooled to 0° C. Water (68 μL) was added and the mixturewas stirred for 10 minutes. Sodium hydroxide 15% aqueous solution (75μL) was added and the mixture was stirred for a further 15 minutes.Finally water (227 μL) was added and the solution was filtered through apad of Celite and rinsed with EtOAc. The two layers were separated andthe aqueous layer was extracted twice with EtOAc. The organic layerswere combined and washed with saturated brine solution, dried overanhydrous sodium sulfate, filtered and the concentrated in vacuo toyield 235 mg (89% yield) of the desired amine product 22. This materialwas used without further purification.

Synthesis of compound 23:

To a stirred solution of compound 22 (117 mg, 0.671 mmol) indichloromethane (6.7 mL) at room temperature was added dropwisetriethylamine (140 μL, 1.00 mmol, 1.49 eq.) followed by acryloylchloride (109 μL, 1.34 mmol, 2.0 eq.). The reaction mixture was stirredat room temperature for 4 hours and the solvent and reactants wereremoved in vacuo. The crude product was purified by flash chromatography(gradient, 0% to 40% EtOAc in hexanes) to yield 77 mg (50% yield) of thedesired acrylamide 23.

Compound 23: ¹H NMR (200 MHz, CDCl₃): δ 7.50 (m, 2H), 7.25 (m, 2H),6.80-6.60 (m, 1H), 6.35-6.40 (m, 1H), 5.75 (t, 1H), 4.80-4.50 (2s fromrotamers, 2H), 3.20-3.00 (2s from rotamers, 3H), 2.30 (s, 3H).

Synthesis of Compound 25:

Commercially available compound 24 (300 mg, 1.32 mmol) was placed in DMF(13 mL), cooled to −40° C. and KOtBu (162 mg, 1.45 mmol, 1.1 eq.) wasadded in portions. The solution was stirred for 90 minutes upon whichcompound 5 (1150 mg, 3.33 mmol dissolved in 3 mL of DMF, 2.3 eq.), wasadded over 15 minutes. The yellow orange solution was stirred for anadditional two hours as it warmed to −28° C. The dark orange solutionwas stirred for 1.5 hours as it warmed to −10° C. and then a further 1.5hours as it warmed to −5° C. The reaction was quenched with diluteammonium chloride (60 mL) followed by water (20 mL). The organic andaqueous layers were separated. The aqueous layer was extracted twicewith ethyl acetate (80 mL). The combined organic layers were backextracted with water (100 mL) to removed DMF, and were dried overanhydrous sodium sulfate. The dried organic layers were filtered andconcentrated in vacuo to give a solid residue. The crude solid waspurified by flash chromatography (24 g of silica gel using 50-100%EtOAc/hex) to yield 150 mg (22% yield) of pure compound 25 as a viscousbright yellow oil.

Compound 25: ¹H NMR (400 MHz, CDCl₃): δ 8.25 (s, 1H), 7.60 (s, 1H), 6.00(d, 2H), 4.10 (m, 4H), 2.92 (t, 2H), 2.70 (t, 2H), 1.05 (m, 4H), 0.00(s, 18H).

Synthesis of compound 7:

Compound 23 (77 mg, 0,336 mmol) and compound 25 (150 mg, 0.279 mmol)were dissolved in dry DMF (2.8 mL) under a nitrogen atmosphere. To thissolution was added in this order: palladium (II) acetate (1.56 mg, 0.007mmol), tri(o-tolyl)phosphine (4.24 mg, 0.014 mmol) andN,N-diisopropylethylamine (74 μL, 0.418 mmol) under a nitrogenatmosphere. The reaction mixture was stirred at 80° C. for 4 hours thencooled to room temperature. Ethyl acetate (20 mL) and a saturatedaqueous solution of ammonium chloride (20 mL) were added and the twophases were separated. The aqueous layer was extracted two more timeswith ethyl acetate. The organic layers were combined and washed withsaturated brine solution, dried over anhydrous sodium sulfate, filteredand the solid concentrated in vacuo. The crude product was purified byflash chromatography (gradient, 50% to 100% EtOAc in hexanes) to yield26.5 mg (14% yield) of the desired compound 7; identical to keyintermediate 7 by ¹H-NMR, MS and HPLC.

Example 2 Solubility Testing

Compounds disclosed herein were tested for aqueous solubility at 25° C.The results are summarized below in Table A. The bis-sodium andbis-ammonium compounds formed unwieldy gels during the solubilityexperiments. Thus their solubilities were not measured. It is alsonoteworthy that the bis-sodium salt, originally amorphous, crystallizedwithin 7 days in aqueous buffer, resulting in a solubility of <5 mg/mL(pH 6.6-7.1).

TABLE A Solubility of Certain Salts in Water at 25° C. (mg free acidequivalent/mL). Water Salt (mg/mL) Comments Bis-Sodium (amorphous)(Compound B) — Forms gels Compound 9 Bis-Ammonium (amorphous) (CompoundC) — Forms gels Compound 14 Bis-Potassium (amorphous) (Compound 11) >100Bis-Potassium (crystalline) (Compound 11) 30-35 Calcium (Compound 13)<0.1 Magnesium (Compound 12) <1 Monobasic Monomethylammonium (15) <20Forms gels Monobasic Dimethylammonium (16) 20-30 Forms gels MonobasicDiethylammonium (18) 50-60 Forms gels Monobasic Triethanolammonium (17) 5-15 Forms gels Bis-Ethanolammonium (crystalline) >300 (Compound A)Compound 10 Compound IV <0.001

Example 3 Solid State Stability Testing

Various compounds disclosed herein have been placed on long-termsolid-state stability protocol. The compounds were stored in glass vialsclosed with PTFE lined caps at 30° C./65% RH, 40° C./75% RH, 50° C. and60° C. (ambient humidity). The results of the study after 4 weeks areshown in Table B1 and after 3 months in Table B2. Appearance and purityanalysis were conducted using HPLC and XPRD. The HPLC analyses wereconducted using standard equipment such as a Agilent HP1100 HPLC(Station ID: LZPES HPLC 04) with YMC-Pack ODS-AQ sub 3 μm, 150×4.6 mm

The bis-ethanolammonium compound (compound A, 10) possessed markedlyimproved solid-state stability over the bis-sodium and bis-potassiumcompounds (see Table B1).

TABLE B1 Solid-state Stability of Salts (4-Weeks) 30° C./ 40° C./ 50°C./ 60° C./ Control* 65% RH 75% RH AMB⁺ AMB Salt % Area^(#) % Area %Area % Area % Area Bis-Sodium 96.4 96.3 84.4 86.8 85.9 (amorphous)(Compound B) compound 9 Bis-Potassium 95.4 87.8 64.3 72.5 50.7(crystalline) (11) Bis-Ethanol- 98.9 98.5 98.2 99.3 98.7 ammonium(crystalline) (Compound A) compound 10 *Control sample stored at ambientlab conditions protected from light. ^(#)% Area = Relative % area ofCompound IV (conjugate base) to the total assay peak area by HPLCanalysis. ⁺AMB = ambient humidity.

TABLE B2 Solid-state Stability of Salts (After 3 Months) 30° C./ 40° C./50° C./ Control* 65% RH 75% RH AMB⁺ Salt % Area^(#) % Area % Area % AreaCompound 10 98.9 98.61 92.75 99.04 *Control sample stored at ambient labconditions protected from light. ^(#)% Area = Relative % area ofCompound IV (conjugate base) to the total assay peak area by HPLCanalysis. ⁺AMB = ambient humidity.

The bis-ethanolammonium compound, Compound A (10) also showeddramatically improved photostability compared to the bis-sodium compound9 (Table C).

TABLE C Control* Photo-stability Salt % Area^(#) % Area Bis-Sodium(amorphous) 96.4 55.9 (Compound B) compound 9 Bis-Ethanolammonium(crystalline) 98.9 97.7 (Compound A) compound 10 ⁺Exposed to 60% of ICHminimum. *Control sample stored at ambient lab conditions protected fromlight. ^(#)% Area = Relative % area of Compound IV(conjugate base) tothe total assay peak area by HPLC analysis.

Additionally, the crystalline bis-ethanolammonium compound 10, (CompoundA) was proven to be stable to gamma irradiation in a range of 25 to 31kGy.

Samples were prepared for XRPD by sprinkling ˜20 mg onto a Si wafer zerobackground plate and pressing the material flat to ensure the surface issmooth and level. The samples were analyzed according the equipmentparameters below.

Bruker D8-Advance XRPD S/N: 202298 Configuration Theta/theta BraggBrentano Incident Beam Soller slit = 2° Optics Divergence slit = 0.2 mmAntiscatter screen = 21 mm Detector Beam Soller slit = 2.5° Optics Nifilter Antiscatter slit = 3 mm Detector PSD: Lynx Eye with 1° windowTube CuKα λ = 1.5418 Å Voltage = 40 kV, Current = 40 mA Scan Parameters2-50° 2θ Step size 0.049° 2θ Time per step 1 s Total Scan Time = 16.5minutes

The XRPD results are shown in FIGS. 3A-B, 4A-B, 5 and 6. There was nochange in crystal form of compound 10 after 3 months at all conditions.Compound 9 is amorphous and exhibits no change over 4 weeks at allstorage conditions. The XRPD for compound 11 shows some changes at 4weeks, particularly for the 40° C./70% RH condition, where sharper peaksappear particularly above 20° 2θ, and underwent significant degradationat 4 weeks at 40/75 (content ˜65%), with many peaks present in itschromatogram.

These studies confirm that: compound 10 is a crystalline salt that isphysically and chemically stable over 3 months at 30° C./65% RH and 50°C. when stored in closed vials and light protected. There was no changein appearance and crystal form over 3 months at all storage conditions,and is also stable to gamma irradiation exposure of 28.6-30.9 kGy;compound 9 is an amorphous salt that is chemically stable over 1 monthat 30° C./65% RH when stored in closed vials and light protected, withno change in appearance and it remained amorphous over 1 month at allstorage conditions; compound 11 is a partially crystalline salt that isnot chemically stable over 1 month at 30° C./65% RH, at 40° C./75% RHand at 50° C. when stored in closed vials and light protected. There wasno change in appearance and it remained partially crystalline over 1month at all storage conditions.

Example 4 Solution Stability Testing

The bis-ethanolammonium compound 10 was solubilized at 25 and 1 mg/mL inwater for injection (WFI) and 5% dextrose in water (DW5) and tested forstability in solution at various temperatures. Solution stability datain WFI is shown in Table D. Solution stability data in D5W is shown inTable E.

TABLE D Solution stability of Compound A (10) in water for injection(WFI) at 25° C. Initial 4 hours 24 hours 48 hours Condition mg/mL %Area^(#) mg/mL % Area mg/mL % Area mg/mL % Area RT 24.05 99.5 23.9 98.822.5 95.2 22.8 91.5  5° C. 25.0 99.3 24.4 98.6 23.1 98.0 −20° C. — — — —24.4 99.2 RT 0.97 99.4 0.94 99.0 0.92 95.5 0.64 92.1  5° C. 0.96 99.40.94 98.1 0.96 98.1 −20° C. — — — — 0.96 99.3 ^(#)% Area = Relative %area of Compound IV (conjugate base) to the total assay peak area byHPLC analysis

TABLE E Solution stability of Compound A (10) in 5% dextrose in water(D5W) at 25° C. Initial 4 hours 24 hours 48 hours Condition mg/mL %Area^(#) mg/mL % Area mg/mL % Area mg/mL % Area RT 24.4 99.6 24 98.923.8 95.6 23 92.1  5° C. 24.9 99.3 24.5 98.7 24.5 98.1 −20° C. 24.6 99.3RT 1.00 99.5 0.99 99 0.96 96.1 0.95 93.1  5° C. 0.99 99.4 0.99 98.8 1.0098.1 −20° C. 0.99 99.3 ^(#)% Area = Relative % area of CompoundIV(conjugate base) to the total assay peak area by HPLC analysis.

Example 5 Comparative Pharmacokinetics

Compounds were tested in both rats and dogs for pharmacokineticparameters and oral bioavailability against the free base (compound IV),tosylate anhydrate salt (Compound Y) and tosylate monohydrate salt(compound Z) of(E)-N-methyl-N-((3-methylbenzofuran-2-yl)methyl)-3-(7-oxo-5,6,7,8-tetrahydro-1,8-naphthyridin-3-yl)acrylamidedesignated as compounds IV, Y, and Z respectively, using the conditionsdescribed below. The structures of the compounds are shown in Table F.

TABLE F Compound Structure Bis-ammonium (C) Amorphous Compound 14

Bis-sodium (B) Compound 9

Bis-ethanolammonium (A) Compound 10

Compound IV (free base)

Compound Y (tosylate anhydrate)

Compound Z (tosylate monohydrate)

Compound IV, Y or Z were administered orally as a suspension using 80%PEG400, 0.5% carboxymethylcellulose or OraPlus as vehicles. Whencompound IV, Y or Z were administered intravenously, a solution of 40%2-HP-β-cyclodextrin in PBS was used as the vehicle, in order to achievea composition for intravenous administration. For human use however itis noted that such a cyclodextrin formulation would be toxic andunacceptable for treatment.

Bis-ammonium, bis-sodium and bis-ethanolammonium compounds (Compounds14, 9 and 10) were administered both orally and intravenously as asolution in 5% dextrose in water, normal saline or phosphate bufferedsaline. For all compounds tested, oral administration was by gavage andintravenous administration by bolus injection or infusion.

All dose levels and plasma concentrations are calculated as Compound IVequivalents. There is no gender effect in dogs on the PK of thesecompounds. However, male rats were not a good model for this studybecause of high clearance rates and low exposures when compared tofemale rats. Therefore, male rats were typically not tested in these PKmodels or excluded from the analyses. FIG. 1A-B show meantime-concentration plots for compound IV after administration ofbis-ammonium, bis-sodium and bis-ethanolammonium compounds (Compounds14, 9 and 10) at a dose level of 5 mg/kg (compound IV equivalents) inmale dogs and female rats. The rapid appearance of compound IV (freebase) indicates efficient conversion of Compounds 14, 9 and 10 toCompound IV in plasma. This was confirmed by simultaneous analysis ofcompound IV and Compound 10 in dog plasma after intravenous dosing withcompound 10 as shown in FIG. 2. Similar results were obtained afterintravenous dosing Compound 10 in rats.

Table G below summarizes mean pharmacokinetic parameters of compound IVafter administration of bis-ammonium (amorphous compound 14), bis-sodium(compound 9) and bis-ethanolammonium (compound 10) in female rats (5mg/kg, Compound IV equivalents). The data indicate that all compoundsare rapidly converted to Compound IV and show comparablepharmacokinetics and oral bioavailability within biological andexperimental variation rates.

TABLE G Pharmacokinetic parameters of compound IV after oral andintravenous administration of compounds 9, 10, and 14 in female ratsTmax Cmax Half life AUC₀₋₂₄ Oral bio- Route Compound (hr) (ng/ml) (hr)(hr * ng/ml) availability Intravenous Compound 14 0.08 5,137 3.31 12,579Compound 9 0.08 7,583 3.79 11,961 Compound 10 0.14 8,070 3.65 16,092Oral Compound 14 1.00 1,333 2.78 12,065 96% Compound 9 3.33 1,907 3.1416,179 135% Compound 10 3.00 2,040 2.20 11,376 71%

Table H below summarizes mean pharmacokinetic parameters of compound IVafter administration of bis-ammonium (amorphous compound 14), bis-sodium(compound 9) and bis-ethanolammonium (compound 10) in male dogs (5mg/kg, Compound IV equivalents). The data indicate that all compoundsare rapidly converted to compound IV and show comparablepharmacokinetics and oral bioavailability within biological andexperimental variation rates.

TABLE H Pharmacokinetic parameters of compound IV after intravenous andoral administration of compound 9, 10, and 14 to male dogs Tmax CmaxAUC₀₋₂₄ Route Compound (hr) (ng/ml) Half life (hr) (hr * ng/ml) Oralbioavailability Intravenous Compound 14 0.58 4,049 3.9 26,659 Compound 90.08 6,216 4.8 35,993 Compound 10 0.09 8,331 4.6 36,083 Oral Compound 141.25 2,632 3.8 20,821 78% Compound 9 0.9 3,123 4.6 23,585 66% Compound10 1.33 2,684 4.6 19,765 54%

Table I below summarizes mean pharmacokinetic parameters of compound IVin both dog and rat following intravenous administration of amorphouscompound 14, compound 9 and compound 10 with comparative data forCompound Z at a dose level of 5 mg/kg (Compound IV (free base)equivalents). The data indicate that compounds 14, 9 and 10 possessed alonger half-life than Compound Z. Notably, compounds 9 and 10 had thelongest half-lives, approximately 60% and 25% longer than Compound Z inrat and dog, respectively. In addition, compound 10 showed the highestexposures (approximately 16% and 11% higher in rat and dog, respectivelythan Compound Z).

TABLE I Pharmacokinetic parameters of compound IV after intravenousadministration of compound 9, 10, and 14 in dog and rat Half Tmax Cmaxlife AUC₀₋₂₄ Route Dose level* Species Compound (hr) (ng/ml) (hr) (hr *ng/ml) Intravenous 5 Rat Compound Z 0.02 10364 2.3 13837 Compound 140.08 5137 3.3 12579 Compound 9 0.08 7583 3.8 11961 Compound 10 0.14 80703.6 16092 Dog Compound Z 0.02 6911 3.6 43551 Compound 14 0.58 4049 3.926659 Compound 9 0.08 6216 4.8 35993 Compound 10 0.08 10973 4.6 48540*(Compound IV molar equivalents, mg/kg)

Table J shows a comparison of the pharmacokinetics of Compound IVfollowing intravenous administration of Compound Z and Compound 10 indogs. Compound 10 showed significantly longer half-lives than Compound Zat doses of 5 and 25 mg/kg.

TABLE J Pharmacokinetic parameters of compound IV after intravenousadministration of compound 10 and Z Dose level (Compound IV molarequivalents, Tmax Cmax Half life AUC₀₋₂₄ Route mg/kg) Species Compound(hr) (ng/ml) (hr) (hr * ng/ml) intravenous 1 Dog Compound Z 0.017 21293.5 8972 Compound 10 1.08^(a) 1262 3.5 6261 5 Compound Z 0.017 6911 3.643551 Compound 10 0.083 10973 4.6 48540 25 Compound Z 0.017 31642 2.587438 Compound 10 2.92^(b) 9482 4.3 68402 ^(a)1 hour infusion; ^(b)4hour infusion

FIGS. 3A and 3B show the results of a comparison of the oralbioavailability of the active compound IV in dog and rat afteradministration of the bis-ethanolammonium compound 10, Compound IV, andCompound Z. As indicated in the Figures, the bis-ethanolammoniumcompound showed significantly higher oral bioavailability than bothcompound IV and Compound Z.

Tables K and L show comparative Compound IV oral bioavailability dataafter administration of compound 10 or Compound Z. Notably, compound 10possessed improved bioavailability (of compound IV) in both dog and ratmodels when compared to Compound Z. Specifically, thebis-ethanolammonium compound 10 provided a 3- to 7 fold higherbioavailability of Compound IV in the dog and 7- to 9-fold higherbioavailability of Compound IV in the rat than Compound Z. Remarkably,as shown in Tables M and N, the bioavailability of Compound IV afteradministration of compound 10 was up to 38-fold higher than afteradministration of Compound IV in the dog and up to 144 fold higher inthe rat. Most significantly, the bioavailability of Compound IV afteradministration of Compound 10 was much less dose-dependent than afteradministration of compound IV and Z as indicated by the increasingrelative bioavailabilities with increasing doses.

TABLE K Dog Oral Bioavailability: Compound IV exposures after Compound10 and Compound Z administration Dose level AUC₀₋₂₄ Relative Oral(compound IV (hr*ng/ml) Bioavailability molar equivalents, Com- Com-Compound 10/ mg/kg) pound Z pound 10 Compound Z 3 3,859 10,727 2.8 1011,289 34,002 3.0 30 25,710 92,408 3.6 100 45,931 226,468 4.9 300 59,269387,188 6.5

TABLE L Rat Oral Bioavailability: Compound IV exposures after Compound10 and Compound Z administration Dose level AUC₀₋₂₄ Relative Oral(compound IV (hr*ng/ml) Bioavailability molar equivalents, Com- Com-Compound 10/ mg/kg) pound Z pound 10 Compound Z 3 1,632 14,642 9.0 105,320 47,360 8.9 30 15,578 135,673 8.7 100 46,437 379,650 8.2 300107,186 782,022 7.3

TABLE M Dog Oral Bioavailability: Compound IV exposures after Compound10 and Compound IV administration Dose level AUC₀₋₂₄ Relative Oral(compound IV (hr*ng/ml) Bioavailability molar equivalents, Com- Com-Compound 10/ mg/kg) pound IV pound 10 Compound IV 3 9,460 10,727 1.1 109,917 34,002 3.4 30 10,059 92,408 9.2 100 10,109 226,468 22 300 10,123387,188 38

TABLE N Rat Oral Bioavailability: Compound IV exposures after Compound10 and Comnound IV administration Dose level AUC₀₋₂₄ Relative Oral(compound IV (hr*ng/ml) Bioavailability molar equivalents, Com- Com-Compound 10/ mg/kg) pound IV pound 10 Compound IV 3 537 14,642 27 101,469 47,360 32 30 2,973 135,673 46 100 4,596 379,650 83 300 5,446782,022 144

Example 6 Comparative In Vitro Activity

The in vitro antibacterial activity of prodrug compound 10bis-ethanolamine salt (prodrug of compound Z/compound IV), compound Zitself, and other comparators were evaluated in a broth microdilutionassay against methicillin-resistant and methicillin-sensitiveStaphylococcus aureus, Enterococcus faecalis, Streptococcus pneumoniae,Streptococcus pyogenes and Escherichia coli.

Bacterial Isolates.

Organisms tested in this study are listed in Table P. Clinical isolatesconsisted of 5 Staphylococcus aureus (MSSA), 3 Staphylococcus aureus(HA-MRSA), 2 Staphylococcus aureus (CA-MRSA), 2 Enterococcus faecalis(VSE), 2 Streptococcus pyogenes, and 2 Escherichia coli (susceptible tomost antibiotics). S. aureus ATCC 29213, E. faecalis ATCC 29212, S.pneumoniae ATCC 49619, and E. coli ATCC 25922 were tested for thepurposes of quality control.

MIC Methodology.

Minimal Inhibitory Concentrations (MIC) values against the selectedisolates were determined using the reference broth microdilution methodaccording to the Clinical Laboratory Standards Institute (CLSI)guidelines.

The MIC was read and recorded as the lowest concentration of drug thatinhibited visible growth of the organism.

TABLE P In vitro antibacterial activity of Compound 10, Compound Z andcomparator antibiotics MIC (μg/ml) Com- Com- Vanco- Line- Cipro-Organism pound 10 pound Z mycin zolid floxacin S. aureus ATCC 29213 40.004 0.5 4 0.5 S. aureus 3104; MSSA >16 0.015 0.5 2 0.25 S. aureus3107; MSSA 8 0.004 0.5 2 0.5 S. aureus 3245; MSSA 16 0.015 0.5 2 0.5 S.aureus 3250; MSSA 8 0.004 0.5 4 2 S. aureus 3856; MSSA 16 0.004 1 2 >64S. aureus 3083; 4 0.004 0.5 2 32 HA-MRSA S. aureus 3086; 16 0.03 1 2 >64HA-MRSA S. aureus 3265; 16 0.004 0.5 2 >64 HA-MRSA S. aureus 2168; 40.004 1 2 16 CAMRSA S. aureus 2294; 16 0.03 1 2 >64 CAMRSA E. faecalisATCC 29212 >16 >2 1 1 0.5 E. faecalis 4158; VSE >16 >2 >64 1 64 E.faecalis 4212; VSE >16 >2 16 1 32 S. pneumoniae ATCC >16 >2 0.12 1 0.549619 S. pyogenes 6179 >16 >2 0.25 1 0.5 S. pyogenes 6528 >16 >2 0.25 10.5 E. coli ATCC 25922 >16 >2 >64 64 0.008 E. coli 2214 >16 >2 >64 >640.015 E. coli 5255 >16 >2 >64 64 0.008

As shown in Table P, compound 10, a prodrug of compound Z showed500-4000 times less activity than Compound Z against a panel of 11 S.aureus strains. (This negligible activity is probably due to traces ofCompound IV (˜0.1%) in compound 10 API.) In part by virtue of theprodrug nature, compound 10 shows no inhibition of S. aureus FabI; noinhibition of non-staphylococcal species, as does compound Z. Thecontrol antibiotics show the expected activity against all bacterialspecies tested.

Example 7 Preparation of N-Boc Amino Acid Chloromethyl Esters (26), theCorresponding Prodrug N-Boc Amino Acid Esters (27) and the CorrespondingProdrug Amino Acid Esters (28)

The esters can be prepared as in Scheme 3:

To individual two-phase solutions (50 mL water and 50 mLdichloromethane) of sodium bicarbonate (52 mmol, 4 equivalents),tetrabutylammonium hydrogensulfate (1.3 mmol, 0.1 equivalents) and theBOC-protected amino acids that are individually N-BOC-glycine,N-BOC-L-alanine, N-BOC-L-valine, and N-BOC-L-proline (13 mmol, 1equivalent each) at 0° C. was slowly added (15.6 mmol, 1.2 equivalents)of chloromethyl chlorosulfate in 15 mL of dichloromethane each. Theslurries were stirred for 12 hours as they warmed to room temperature.The organic layers were separated and the aqueous layers wereindividually extracted once more with 50 mL of dichloromethane. Theindividual combined organic layers were then dried over anhydrous sodiumsulfate, filtered and the filtrates concentrated in vacuo to yield thecrude products as residues. The residues were individually purified byflash chromatography (25% EtOAc/hex with 3% NEt₃ (critical buffer). Thisyielded pure materials as colorless oils which were each >95% pure by ¹HNMR:

Compound 26a: ¹H NMR (400 MHz, CDCl₃): δ 5.50 (s, 2H), 5.10 (bs, 1H),3.95 (d, 2H), 1.40 (s, 9H).

Compound 26b ¹H NMR (300 MHz, CDCl₃): δ 5.73 (dd, 2H), 4.95 (s broad,1H), 4.35 (m, 1H), 1.47 (s, 9H), 1.42 (d, 3H).

Compound 26c: ¹H NMR (400 MHz, CDCl₃): δ 5.68 (dd, 2H), 5.00 (bs, 1H),4.20 (m, 1H), 2.20 (m, 1H), 1.40 (s, 9H), 1.00 (d, 3H), 0.95 (d, 3H).

Compound 26d ¹H NMR (400 MHz, CDCl₃): δ 5.75 (m, 2H), 4.35 (m, 1H), 3.50(m, 2H), 2.25 (m, 1H), 1.95 (m, 3H), 1.41 (s, 9H).

General Procedure for Synthesis of Compounds 27:

Individual reactions of Compound IV (5 mmol, 1 equivalent) were placedin DMF (50 mL) at room temperature and cesium carbonate (6 mmol, 1.2equivalents) was added to each reaction in portions. The solutions werestirred for 30 minutes upon which (6 mmol, 1.2 equivalents) of theindividual chloro reagents, 26 (dissolved in 5 mL of DMF), were addedand the yellow solutions were stirred overnight at room temperature. Thereactions were quenched with dilute aqueous ammonium chloride (1 L)followed by water (2 L) and the quenched mixtures were individuallyextracted twice with ethyl acetate (EtOAc) (2 L). After the organiclayers were back-extracted with water (1 L) to remove DMF, the organiclayers were individually dried over anhydrous sodium sulfate, filteredand the filtrates individually concentrated in vacuo. The crude productswere individually purified by flash chromatography (50-100% EtOAc/hex)to yield pure materials as light-colored oils:

Compound 27a ¹H NMR (300 MHz, CDCl₃): δ 8.38 (d, 1H), 7.68 (m, 2H), 7.50(d, 1H), 7.41 (d, 1H), 7.25 (m, 2H), 6.90 (d, 1H), 6.25 (s, 2H), 5.05 (sbroad, 1H), 4.85, 4.75 (2s, 2H), 3.90 (bs, 2H), 3.25, 310 (2s, 3H), 2.98(m, 2H), 2.78 (m, 2H), 2.32 (s, 3H), 1.42 (s, 9H).

Compound 27b ¹H NMR (300 MHz, CDCl₃): δ 8.38 (d, 1H), 7.68 (m, 2H), 7.50(d, 1H), 7.41 (d, 1H), 7.25 (m, 2H), 6.90 (d, 1H), 6.30, 6.25 (2s, 2H),5.05 (s broad, 1H), 4.85, 4.75 (2s, 2H), 4.30 (s broad, 1H), 3.25, 310(2s, 3H), 2.98 (m, 2H), 2.78 (m, 2H), 2.32 (s, 3H), 1.42 (s, 9H), 1.25(d, 3H).

Compound 27c ¹H NMR (300 MHz, CDCl₃): 8.42 (m, 1H), 8.10-7.90 (m, 2H),7.60 (d, 1H), 7.58 (d, 1H), 7.41 (d, 1H), 7.30-25 (m, 2H), 6.30, 6.25(2s, 2H), 6.05 (s broad, 1H), 4.95, 4.85 (2s, 2H), 4.40, 4.10 (2m, 1H),3.25, 310 (2s, 3H), 2.98 (m, 2H), 2.78 (m, 2H), 2.32 (s, 3H), 2.05 (m,1H), 1.42 (s, 9H).

Compound 27d ¹H NMR (300 MHz, CDCl₃): δ 8.40 (d, 1H), 7.66 (m, 2H), 7.50(d, 1H), 7.41 (d, 1H), 7.25 (m, 2H), 6.89 (d, 1H), 6.22 (m, 2H), 4.83,4.73 (2s, 2H), 4.25 (m, 1H), 3.45 (m, 2H), 3.25, 310 (2s, 3H), 2.95 (m,2H), 2.78 (m, 2H), 2.32 (s, 3H), 2.25 (m, 1H), 1.95 (m, 3H), 1.20 (2s,9H), 1.00, 0.95 (2d, 6H).

General Procedure for Synthesis of Compounds 28

Compounds 27 (0.1 mmol, 1 equivalent) were individually dissolved indichloromethane (10 mL), cooled to 0° C. and hydrogen chloride (0.4 mLof a 4M solution in dioxane, 16 mmol, 16 equivalents) was added dropwiseto each reaction. The individual solutions were stirred for 45 minutesas they warmed to room temperature. The solutions were then concentratedin vacuo to yield sticky oils. Acetone (5 mL) was added to theindividual oils and these solutions were vigorously stirred until theoils solidified. The individual solids were filtered and air dried toyield pure materials which were >95% pure by ¹H NMR, LRMS and HPLC.

Compound 28a: ¹H NMR (400 MHz, CDCl₃): δ 8.95 (s broad, 2H), 8.30 (d,1H), 7.50-7.20 (m, 7H), 6.15 (s, 2H), 5.00, 4.8 (2s, 2H), 4.40 (m, 1H),3.90 (s, 2H), 318, 2.90 (2s, 3H), 2.95 (m, 2H), 2.75 (m, 2H), 2.25 (s,3H).

Compound 28b ¹H NMR (400 MHz, DMSO d₆): δ 8.50 (d, 1H), 8.35 (s broad,2H), 8.22 (d, 1H), 7.55 (m, 2H), 7.45 (m, 1H), 7.25 (m, 3H), 6.15 (s,2H), 5.00, 4.80 (2s, 2H), 4.10 (m, 1H), 3.18, 2.90 (2s, 3H), 2.95 (m,2H), 2.75 (m, 2H), 2.25 (s, 3H), 1.30 (d, 3H).

Compound 28c: ¹H NMR (400 MHz, CDCl₃): δ 8.60-8.40 (m, 3H), 8.20 (m,2H), 7.70-7.10 (m, 6H), 6.20, 6.10 (2d, 2H), 5.00, 4.80 (2s, 2H), 3.90(s, 1H), 3.18, 2.90 (2s, 3H), 2.95 (m, 2H), 2.75 (m, 2H), 2.25 (s, 3H),0.90 (m, 3H).

Compound 28d ¹H NMR (400 MHz, DMSO d₆): δ 9.80 (s broad, 1H), 8.95 (sbroad, 1H), 8.50 (d, 1H), 8.23 (d, 1H), 7.55 (m, 2H), 7.45 (m, 1H), 7.25(d, 3H), 6.15 (s, 2H), 5.00, 4.70 (2s, 2H), 4.28 (m, 1H), 3.18 (m, 5H),2.95 (m, 2H), 2.75 (m, 2H), 2.25 (s, 3H), 2.18 (m, 1H), 1.90 (m, 3H).

REFERENCES

All publications and patents mentioned herein, including those itemslisted below, are hereby incorporated by reference in their entirety asif each individual publication or patent was specifically andindividually incorporated by reference. In case of conflict, the presentapplication, including any definitions herein, will control.

EQUIVALENTS

While specific embodiments of the subject invention have been discussed,the above specification is illustrative and not restrictive. Manyvariations of the invention will become apparent to those skilled in theart upon review of this specification. The full scope of the inventionshould be determined by reference to the claims, along with their fullscope of equivalents, and the specification, along with such variations.

Unless otherwise indicated, all numbers expressing quantities ofingredients, reaction conditions, and so forth used in the specificationand claims are to be understood as being modified in all instances bythe term “about.” Accordingly, unless indicated to the contrary, thenumerical parameters set forth in this specification and attached claimsare approximations that may vary depending upon the desired propertiessought to be obtained by the present invention.

We claim:
 1. A compound represented by:

or a pharmaceutically acceptable salt thereof.
 2. A pharmaceuticallyacceptable composition comprising the compound of claim 1 and apharmaceutically acceptable excipient.
 3. The pharmaceuticallyacceptable composition of claim 2, wherein the composition is a powder,tablet, pill, or capsule.
 4. The pharmaceutically acceptable compositionof claim 2, wherein the composition is a sterile aqueous composition. 5.A pharmaceutically acceptable composition suitable for oraladministration, comprising a compound of claim 1 and a pharmaceuticallyacceptable excipient suitable for the oral administration.
 6. Apharmaceutically acceptable composition for intravenous administration,comprising a compound of claim 1 and a pharmaceutically acceptableexcipient suitable for the intravenous administration.
 7. A compoundrepresented by formula I:

wherein, R₁ and R₂ are each independently selected from the groupconsisting of hydrogen, an alkali metal, NH₄ ⁺, NH₃ ⁺—(R₃), NH₂ ⁺—(R₃)₂,and NH⁺—(R₃)₃, or R₁ and R₂ taken together are an alkaline earth metal;and R₃ is independently selected from the group consisting ofC₁₋₆alkyl-, hydroxyC₁₋₆alkyl-, phenyl and benzyl.
 8. The compound ofclaim 7, wherein R₁ and R₂ are each NH₃ ⁺—(R₃).
 9. The compound of claim7, wherein one of R₁ and R₂ is H; and one of R₁ and R₂ is NH₄ ⁺ or NH₃⁺—(R₃).
 10. The compound of claim 7, wherein R₃ is —CH₂CH₂OH.
 11. Thecompound of claim 7, wherein R₁ and R₂ are an alkali metal.
 12. Thecompound of claim 11, wherein the alkali metal is selected from thegroup consisting of lithium, sodium and potassium.
 13. The compound ofclaim 7, wherein R₁ and R₂ taken together are an alkaline earth metal.14. The compound of claim 13, wherein the alkaline earth metal iscalcium or magnesium.
 15. The compound of claim 7, wherein the compoundis represented by:


16. The compound of claim 7, wherein the compound is represented by:


17. The compound of claim 7, wherein the compound is represented by:


18. The compound of claim 7, wherein the compound is represented by:


19. A method of treating a bacterial infection, comprising administeringto a patient in need thereof a composition of claim 2 to treat thebacterial infection.
 20. The method of claim 19, wherein the bacterialinfection is a Staphylococcus aureus infection.
 21. The method of claim20, wherein the Staphylococcus aureus is methicillin-resistant.
 22. Themethod of claim 19, wherein the patient is a human.
 23. The method ofclaim 19, wherein administering is selected from the group consisting oforally administering, intravenously administering, subcutaneouslyadministering, topically administering, and administration byinhalation.
 24. The method of claim 19, wherein administering is orallyadministering.
 25. The method of claim 19, wherein administering isintravenously administering or subcutaneously administering.
 26. Themethod of claim 19, further comprising administering to said patient acompound selected from the group consisting of an oxazolidinone,vancomycin, teicoplanin, a glycopeptide, a penicillin, a cephalosporin,a puromutalin, a fusidane, a lincosamide, rifamycin, and arbekacin. 27.The method of claim 19, further comprising administering to said patienta compound selected from the group consisting of linezolid, daptomycin,teicoplanin, and telavancin.
 28. The method of claim 19, furthercomprising administering to said patient a compound selected from thegroup consisting of quinolones, fluoroquinolones, carbapenems,aminoglycosides, tetracyclines, streptogramins, and macrolides.
 29. Amethod of preparing a compound represented by formula II:

the method comprising: contacting a compound of formula III with acompound of formula IV or salt thereof; wherein: formula III isrepresented by:

formula IV is represented by:

wherein: X represents a leaving group; and Pg represents a protectinggroup.